I am getting good battery life after i did the following thing

http://talk.maemo.org/showthread.php...676#post816676

1 Install this software.
2 Charge ur n900 switched off, usually one hour b4 going to bed.Once the green is on. on it and see it for your self.

you don't even have to worry about switching to 2g and 3g. i get normal 12 hours + of normal use( web, music, calls). hope it helps

Thankx to debernardis for such a good software.