Maemo does look promising if app developers bite on it. Right now it has some serious limitations, doesn’t work in portrait mode being the major one. Also, the hardware definitely seems like an afterthought only done to get the OS out the door.
A virtual keyboard only Maemo device that has portrait mode (and ideally a slightly bigger battery) would be pretty solid. I have heard rumors that they are working on a N920 to be virtual keyboard only. Hopefully the software tweaks are in the pipeline too.
The great thing about Maemo is that there is a ton of software already out there that can run on the platform.