There's been some concerns among mobile phone users who are interested in the iPhone 3G about the battery life. PC World Test Center did battery tests that include the 3G iPhone and several 3G phones from all US carriers. These phones include the Samsung Instinct, HTC Touch Dual, LG EnV, ATT Tilt, the Palm Centro and more. Here is more info on the test:
"The battery life on Apple's new 3G iPhone isn't great, but it beats that of other 3G smartphones we've seen. PC World's Test Center ran it through our standard talk-time battery life test, and found that on average it ran 5 hours and 38 minutes, which we consider to be fair."