Best thing...Root your phone, then install "SetCPU" and setup profiles to shut down your processor speed, especially when it is turned off. This, along with basic battery suggestions, found with a search, will make a huge difference...I now get well over 12-16 hours of juice, with my normal usage...how YOU USE your phone, will of course dictate maximum battery life...but I have to tell you...I am really impressed with SetCPU (and root in general
)...
If you choose to not root, then search...and ye shall find many good battery tips, like the one above
