I don't think the update has addressed any battery issues at all. Some were reporting that their battery meter went up after the update, but that's because the phone reboots during the update. And many of us were already reporting that the battery jumps up after doing a power-down.
Especially since they didn't specifically mention it in the release notes, I think it's safe to assume this update should not really affect battery life either way. Hopefully, in a future update they will address the sporadic battery issues.
Personally, battery life is a mixed bag. Sometimes I'm surprised it lasts longer than I expected. Other times, it seems to die suddenly after getting to 20-30%. I'm not sure what's going on, but if it was just consistent, I think the battery life is actually pretty decent. I'd say on average, about on par with my previous iPhone 3GS, but definitely not close to the iPhone 4.