I have yet to take the plunge into the dark abyss that is the iPhone 4S. I presently own a 4 (or does the 4 own me??) I've had this phone since initial release and have loved it like I do my girlfriend (just don't tell my girlfriend)... I've heard about the shoddy battery performance on the 4S, hence my hesitation.
BUT...
I felt the need to chime in here. I, like the rest of the modern world, have upgraded to iOS5. Ever since the upgrade, my 4's battery life has decreased DRAMATICALLY!!! I am experiencing the same issues that many of the 4S users are. Within a half hour of being off the charger, the battery is at 89% with virtually NO use. Now, for all I know, this has been mentioned in the 200+ pages of posts here. But I lack the motivation and desire to read 200 pages of the same issues. But I really wanted to acknowledge that this is NOT a 4S problem (as far as I go). This is absolutely an iOS5 issue. One of the main culprits (at least in my case) was the WiFi sync. It seemed that was completely tanking the battery. However, even after disabling, I still experience low performance, just not as bad.
It just boggles my mind that Apple can host over 200 pages of complaints about 1 specific issue, yet will NOT acknowledge the issue as an actual issue!!! I won't even get into the fact that no apparent testing seems to have been done BEFORE iOS5 made it to the market, with reference to battery life. I expect this kind of performance from a snot-nosed, immature child of a company. NOT a tech giant, known for sleek astetic and intense forthinking!!! I am thoroughly disappointed!!!
Again, if this was already mentioned in this sea of comments, then forgive the repetition. This is the first time I've actually taken to any forum with my gripes, so personally, that's saying something about the calibur of prioduct being released nowadays!!!