If basic phone functionality was not working, I would have returned the device last Friday. My N900 is in part replacing my work phone, it [b]HAS[b] to work because at time I go oncall. Bluetooth headsets, AD2P streaming, SMS and voice calls work well enough for me.

And since you asked indirectly I'll mention those annoying behavious I mentioned. First is the FM transmitter being kicked off when a bluetooth headset connects to the N900. (specifically it's the hands free feature of my car's stero system). Knowing how the sound subsyste works in Maemo, I understand why but I'm not happy with it. I think it should only diable the FM xmitter is a headphone bluetooth device connects. We really need a sound mixer so an advanced user has control over how sound is mixed on the N900 (and other Maemo hardware).

A missing phone feature, the big one for me is voice dialing. That's the one I really miss. I had vowed my next phone would have it since Palm decided not to add it into their Treos. But I went and bought the N900 anyway.

Other missing features I'd like to see user definable profiles that extend well into the other apps. (For instance disable Email app's auto updating at night. And enable it during the day. An other example is disable/enable each account individually for each profile.) That's all I got off the top of my head.