45wpm on n900, 60wpm on netbook, probably 80 or so on a real keyboard.

Very odd looking. I can see how it would increase typing proficiency though. Would take some time getting used to, but once you did.

http://wiki.maemo.org/Remapping_keyboard
That link should tell you almost all you need to know. Feel free to ask if you have any questions. If you're curious, personally, my keyboard is mapped where I have:
Shift+Fn+Q = plus-minus sign
Shift+Fn+W = multiplication sign
Shift+Fn+E = division sign
Shift+Fn+R = less-than-or-equal
Shift+Fn+T = greater-than-or-equal
Shift+Fn+Y =* apostrophe-like accent that slants along like so: /
Shift+Fn+U =* apostrophe-like accent that slants along like so: \
Shift+Fn+I = Infinity sign
Shift+Fn+O =* Degree sign
Shift+Fn+P = Generic currency symbol.
Shift+Fn+, = not-equal sign
Shift+Fn+A = Guillemot left
Shift+Fn+S = Guillemot right
Shift+Fn+D =* Caron (This thing--> ^ )
Shift+Fn+F = Less than
Shift+Fn+G = Greater than
Shift+Fn+H =* Tilde (This--> ~ )
Shift+Fn+J = percent sign ( % )
Shift+Fn+K = (same as J. There's a bug that takes Shift+Fn+J and Shift+Fn+J as both being pressed at once when you press just one of them - I edited that "Known Bugs" part into the wiki btw. It was known before, but no one bothered. I left K unmapped, so both of them yield %+nothing, which in turn just types out %.)
Shift+Fn+L =* single above-dot accent mark
Shift+Fn+. =* double-dot accent mark
Shift+Fn+Z = Yen symbol
Shift+Fn+X = (Same as Z - same bug as J and K have.)
Shift+Fn+C =* the downwards-pointing equivalent of ^
Shift+Fn+V = {
Shift+Fn+B = }
Shift+Fn+N = [
Shift+Fn+M = ]
Shift+Space = |
Shift+Fn+Space = Broken | - looks like the |, but has a small gap in the middle.
Fn+Enter = Tab
Fn+Backspace = Delete
Shift+Fn+Backspace = Esc
Fn+Up = PgUp
Fn+Down = PgDown
Fn+Left = Home
Fn+Right = End

The * means it's a 'dead' key. That means the first press of it doesn't do anything, the second press of the same key combines to actually type that character by itself - but if you follow it with another key, if that other key can be combined with the aforementioned dead key, it'll type the accented one (I also made the N key - the one with the " on Fn+N - type a dead 'double acute' accent. The N900 seems to type the same exact character when typing the double acute accent by itself as the normal double quote. So if I have to type the ", it's two presses of Fn+N, but to me that's a fair trade for the extra available-at-hand accented letters should I want to type them.

This made just about every symbol in the special character keyboard unnecessary, so I used the "Keyboard Mod." app to edit that. (You can't edit the special symbol keyboard as easily as the hardware keyboard's layouts, unfortunately.)

Because your two thumbs between them have to cover far less distance. There are SOME cases where you are going to be able to type better on a keyboard guaranteed - but those are usually specific (hold-multiple-keys-down) combinations. Corner cases, really. The only time I encounter them is when I need a Ctrl+Shift+Key combination, because then both hands have to be on the left side, and when I need a capitalized letter but the normal press-once-to-capitalize-next-letter aspect of the input method glitches.

Anyway, what this means is this: when you're completely 'on the ball'/'the top of your game'/(insert other cliche phrase here) - basically, when you're performing optimally while typing and have ingrained it mentally so damn well that you've basically pushing the boundaries of human physical ability for speed and precision while typing, then YES, the normal hardware keyboard is undeniably better than the thumb-only one. But here's the thing - you're almost never going to type like that. Not unless you have something to well memorized/thought-out before-hand, that you don't need any pauses what so ever to think, contemplate, remember, or edit what you just typed because after typing out a word you think of a better one.

Normally, you aren't going to be pushing those limits, and when you're good - but not amazing - at typing, your upper binding factor on speed will probably be something other than typing speed.

Hmmm. I did some quick trials:

N900:
46 WPM (3 Mistakes)
44 (2 mistakes)
After familiarizing myself with the text I was about to type for a bit:
43 (6 mistakes - crap run - people distracted me)
50 (3 mistakes)

Computer runs (laptop, large enough that it's just as big as my normal keyboard... prob'ly a bit more comfortable):
59 (1 mistake)
51 (1 mistake)
When familiarizing myself with the text some:
70 (1 mistake)
61 (1 mistake) Crap run - I made another mistake early in, that I went back to correct, right-clicked, had to click out of the menu that appeared, etc.

Here's the thing - I grew up from just before 8th grade until 11th grade daily, constantly, on forums, typing long posts on any number of topics (mostly politics and philosophizing, ethical debates, etc) - so I have a relatively decent amount of typing experience. In the years since I haven't typed nearly as much, so I am no where near as proficient at typing as I used to be, and I actually do consciously notice it during these typing speed tests. However, this means that typing on normal keyboards is something I've been doing for about 7 years. I've had the N900 for around 6 months, maybe a bit more. Yet in that time I have gotten to the point where my typing range on the N900 is about 10wpm lower. When I'm doing what I would consider pretty damn good, on normal keyboards I overcome that a little bit too, but the fact of the matter is, that rarely happens.

When I type normally on the N900, it's things like this post - other posts, chat room conversations, text messages (this is me, so the former two are long too, mostly), and essays for some of my classes. In other words, it's not like the typing speed tests I just did where I'm copying something quoted from some obscure novel from 60 years ago when the very wording and syntax is mind-stumbling-inducing different than what I myself am used to typing.

From personal experience at typing my essays on FreOffice on the N900 vs office suites on my laptop/computer, I am sure that there are moments when I type faster on the computer than on the N900. But on average, the amount of mental time spent articulating my ideas as I write (I don't do drafts) typically lowers me down to 45-55 wpm anyway. The end result is that the bursts of typing out words I clearly have in my mind differ by seconds at most when I type them on the N900 vs the computers I have - however, the N900 trumps this by the sheer convenience of self-relocation/repositioning that it brings to the table. I can't up and take my desktop, and as much as laptops might claim portability, even if I drop all the cords and the mini ubs mouse I use, and the battery lasts me for the entire essay write, every relocation still requires lots of fiddling with something relatively bulky, and I can't do things like lay down flat on my back while holding the laptop up in front of my face. Either it'll fall, or I'll manage to hold it until my arms get tired, but either way, I won't get any typing done.

So I concede that in pure typing speed, I am currently slower than on full keyboards (although I suspect a large part of that is the sheer amount of time I had to get used to full-hand typing, vs. hardware-keyboard-with-thumbs typing). However, in practice, they either even out, or, depending on use-case, the N900 overtakes laptop.

Yeah, that's what I was wondering also. And I (personally) don't like the Ctrl, Shift, Uppercase keys. For Blackberry, a longer press on a key changes it to CAPS works faster.

Meh. I personally love having said keys. (TL;DR summary of what I said above re: only-thumbs: Smaller distance = less need for other fingers, and unless you're pushing the limits of physically possible typing speed for humans, thumbs-only isn't going to be your physical limitation... assuming sufficient endurance for thumbs, of course.)

If it were up to me, you'd have the option of configuring it, like you have the option of switching hold-key-to-get-FN-character on/off in gconf right now. Maybe even a "hold 1 second = shifted, hold 2 second = fn'ed, etc"... with configurable time-outs, ideally.

Myself, though, after PR1.2 added that hold-button-to-get-FN-character option, I found that it was FAR slower to do that, then hit Fn key and then the button. To me such methods feel like how you would probably feel if right now, when typing "I", you had to hold down the i key and ...wait... until it capitalized and then keep typing. When there's this lovely shift key right there. Make the time-outs shorter, and of course you're stepping on the people who's internal 'timers' are slower so they have difficulty timing the non-shifted/Fn'ed button.

But that's why I said give people options, and make as much of the end-user interface as configurable as possible.

usually i type at 85000 rpm lol, like a boat engine

I was slow at first, eventually got faster and did less typos. my PC too got pretty useless when i got n900 and i use my PC only for gaming or downloading stuff(for N900 ) or backing up/flashing my phone. i work as a snowmobile safari guide and N900 is pretty useful with all the map applications and the ease of note taking. if i lose my thumbs somehow, i would propably kill my self and be buried next to my phone

Tested at about 38 wpm on n900, vs 42 on netbook. My only gripe is that I thend to hit 'm' instead of the space bar.

It's also the agony of making frequent mistakes between the Fn and the Shift keys (I confuse them a lot). Maybe I just need to get used to the N900 keyboard. I migrated from E65 - standard 12 keys which was VERY effective to sms while driving - but awefully slow when typing long stuffs - which I never had to with the E65 (no note taking use on that phone).

On N900 im getting around ~40 words per minute, on Compuuter Keyboard 60-70, measured with several online speed tests.

LMAO!

I type with the grace of a Piano player. I'm like the Elton John of N900 keyboards.