I agree with Rabilon. I only bought a N900 a couple of months ago, when I saw a really good deal, which actually reduced my monthly phone bill by almost a third.
I always thought the N900 would be too small, keyboard too fiddly etc. I had actually fingered a demo mockup back in Feb, and thought that.

Gadget lust finally took over, and you know what, I have never touched the N810 since. It's still there, and charged.

The N900 was definately a worthy upgrade from the N810. The next update is seemly due imminently, and from what I have read does not add much in the way of extras, but will have a load of fixes which should make the device even slicker etc.

I do not think you will be disappointed.