My battery has only dropped one percent in 30 minutes so it's early to say for sure, but I think battery life is better!
Keep this kind of comments coming guys, want to be sure that I can install iOS 9 beta on my iPhone 6.
Tried the first beta from the release two weeks ago, but battery life was terrible! Beta or not, it was just too worse. Hope beta 2 really fixes that. I don't even care that much about performance, I can have it if it's slower. But battery life should at least not be so terrible that it drops 1% every single minute, even when iPhone is not in use at all.