[glhaynes]

Yeah - lots of people are saying they're having worse battery performance on the 4S or iOS 5 (lots of people aren't, too), and then lots of those people are claiming lots of different things such as turning off various features (and also not doing anything different at all!) has dramatically helped. In other words, essentially no science is being done and no one to my knowledge can say anything definitively yet, but lots of folk remedies are being tweeted. Assuming there's not a bug in the geofencing code, it shouldn't use too much more battery at all because it only goes out to the GPS when available cell towers—which are being constantly communicated with anyway—change.

[hartror]

I am getting way better battery performance that I was getting on my 2.5yo 3G with iOS4 that I upgraded from so I am yet have an issue with it.