I was pretty surprised by the thickness and weight of the N900 when I saw the first pics. Yes, sometimes it might be better to be a bit thicker for grip, but with some kind of invisible shield and/or case, it will be pretty chunky to tote around. I wonder what contributed to the additional thickness...
I'm gonna go against the general opinion in this thread and say I wish it was at least three mm thinner. The N900 is a couple of mm thicker than my current phone, and I think my current phone is a tad on the chubby side.
Somewhat like the owner.
But any way I calculate it, the thickness of the N900 is thinner than the thickness of that phone plus the N810. So it's still a step in the right direction.
Also, the lower weight is welcome with me, since I sometimes get tired in the hands when I use it for hours. Not sure that it really will make any difference, but I welcome it anyway.
Like bikes and steaks, thickness is relative to the benefits it brings. The N900 fits in my pockets and for me it feels more or less in the same league as the very popular phones I have been using since I joined Nokia (5200, N95, N81, N82, E71). Also as a user of the three Internet Tablets I'm just amazed about the size reduction increasing the features and keeping the same type of user experience.
I'm not an engineer and I don't even know exactly what are the layers that bring that thickness but with a high density display, hardware keyboard, stereo speakers, 5Mp camera and a build quality that passes the Nokia drop tests I actually feel our hardware designers and engineers did a great job (again).
PS: also think about all the people that usually don't carry the phone in their pockets e.g. most women and there is plenty of them.
While I do think the N900 is both too big and too heavy for me to carry it around every day, I must admit that my current phone (6110 Navigator) is even thicker: 20mm as compared to the N900s 18-19mm. (It's still smaller, though, and not as heavy).