mine is about a day a charge. Sometimes its got 40-50% left at the end of the day, so I am ok with it.
I have found that since the GB update, its actually better.
Now that said, I have been using the voice typing thing more often now, where instead of typing, I just talk. I find that uses a SHED load of battery. If I do a few messages voice typed instead of finger typed, my battery will drain much faster.
I also have wigets for turning on GPS, WiFi and Blutooth. If I am not in the car, I turn off blutooth. If I am not at home, work or other known WiFi area, I turn that off. If I am not actually using something that benefits from GPS, I turn that off. Those 3 radios use lots of power and if they are not needed, shut em down.