It will probably not last a day whith normal use. The n95 didnt last a day the n95 8gb didnt and the n96 didnt either. The n900 has a 1320 mah battery 400 bigger then the n96. but i guess it uses atleast twice as much power when used then the n96.

Power optimisation is perfect... when not using the phone... you cant cut back speed to save power? atleast not when using the phone. same as for backlight and stuff. all the options possible are allready used in all the phones. like keyboerd backlight turns off when there is enough light. and background light is dimmed when its dark. Nice features but even with these features you save half an hour max! and probably even less!

What i dont get is why they always begin about "if we put in a bigger battery the phone will become too big" i couldnt really care less if the n900 would be 5 mm thicker and having a 2500 or 3000 mah battery.

Im still waiting for a phone that can last for atleast 8 hours browsing the web... my n96 right now is emty in half an hour (when fully charged) and im afraid the n900 will get the same problem

There is a program called energy profiler its free and lets you see the amount of Watts used by the phone.