I just started getting really good battery life so I am also hesitant to update. I feel like I remember thing happening last year in one of the 4.0 updates that made the battery worse. I know this is update is obviously said to make it better, I just don't have any problems with the phone now finally so I don't really want to change it.
I didn't have problems at all but I updated to see the OTA lol, actually thought it went smoother then some phone I had in the past the bad thing only on wifi but all good battery life probably stay the same or idk
If you want to jailbreak soon then no. Otherwise update. I never had battery problems, why would I bother and besides I'm missing my jailbreak. The hackers will use Charlie miller found exploit for untether jailbreak. This update fixes that hole.