Read my post history, I outline every app/setting I use to maximize battery life and performance. I have an extended battery on the stock ROM (with all the bloatware frozen); I'm currently at 10hours 11minutes and 42s since unplugged, with 90% battery left. Granted, 6 of those 10 hours were while I was asleep, but I still regularly see two days of moderate usage, 3 of light. For me, moderate usage is 3-5 hours of MP3s, some web browsing, running a few apps (games, skymap, appbrain, etc), some wifi, and maybe some navigation if I happen to be lost. I can run mp3s at work ALL DAY (7-9 hours) and still have 30-50% battery left when I get in my car (depending on what else I've been doing).
short rundown: I rooted (google z4root if you're unfamiliar), I used TitaniumBackup (Donate) to freeze all the bloatware that comes preinstalled on the phone, and just eats battery/processor time, I used SetCPU to create profiles. For example, when my screen is off, my phone's max processor speed goes down to 600MHz, same if my battery gets over 41C. I keep wifi/bluetooth/GPS turned off except when I'm using them, and 3G is on... roughly half the time I use my phone? I'm not important enough to need constant push email notification, so that's no big deal to me.
