heh,
mine n900 lasts 2,5 days with the following:
- ~ 2 hours a day mp3/flac listening, daily
- ~ 1 hour of wifi usage for RSS, email, porn, whatever; also daily
- ~ 5-10 calls 5 mins each daily
- ~ 5 SMS daily
- ~ 1 hour djvu/pdf reading, daily as well

using autodisconnect/brightness minimum/wifi down when I don`t explicitly need it.

I really find that scenario ok. And don`t having 3g in mine banana republic is became an advantage, hehe