I get 5-6 hours of screen-on time with my Razr Maxx HD. And that's with everything turned on, regardless of whether its in-use or connected or not (wifi on all day, connected or not, Bluetooth on all day, GPS on, automatic map location reporting on, data sync on, LTE on, screen brightness at auto, etc).
It's amazing. The thing I hated most about Android phones is having to micromanage every service and sensor to eek out the last possible milliamp of power from the battery. Since I got the Maxx HD, I can finally experience what an Android phone is supposed to do - and actually use it at full potential all day long.
I will never buy another Android phone with a "standard" battery. And carrying a spare, honestly, I always found to be a huge hassle.