personally i think the droid x battery is good... Im always using it to play music, txt and surf net. I get to school around 8:30, and get home by 6 and still got about 1/2 life maybe in the yellow if I really use it alot... (I always have wifi off, and dimmest brightness)
I had the android Sanyo Zio before this, and id be lucky if the phone would last 4 hours no joke. I think different manufactures play more in the role of battery life, then the "android os" it self...