1. One standard mp3 for a profile (currently there's only one profile besides silent, though the existence of a Profiles item in Settings can tell us that there will be probably more). I couldn't find a way to assign personal ringtones, but maybe there is or will be a way.

2. No voice dialing as reported.

3. I find it comfortable and not heavy, but I don't have 30 mins conversations too N900 is much smaller than N800 as you probably know.

4, 5. Great!