I'm really happy with my N900 and use it extensively as a business smartphone, PDA and as Linux device. There are lots of bugs and silly limitations, but on the whole it's excellent.

I find the form factor (size, keyboard, stylus) very usable and practical too.

Except for two things that stand out:

- Web video no longer works. Usually it's "you have the wrong
flash version" (+ download link (roll-eyes)), but even if that's ok
then the video is very choppy on all sites I've tried for months.
This is sad as the N900 was good at web video when it came out.

- Worry about the USB connector breaking off.

So I would be looking for a replacement device with at least similar functionality to the N900, and those two issues fixed.

Sadly there is no such device at the moment, nor any in development that I know of. There's also no guarantee of being able to get a replacement new N900 when this one breaks.