I was going to stick with it since my iphone 4s was JB....Then it stopped syncing with my itunes.....so I restored it back to stock and updated....the battery is sooo much better now....not sure if I'll ever JB again even when the new untethered version comes out...
I started this thread and I upgraded to 5.1 today in an attempt to address a minor technical problem. The phone is currently bricked as a result (see thread in iPhone 4S forum). I'm working on the problem but I cannot recommend upgrading at the moment.
I haven't updated for the shear reason of not wanting to getting rid of my jailbreak. If I wasn't jailbroken, I would update just because the 1 notification bubble on the "Settings" app is driving me nuts =P
I found the new Cydia tweak Software Update Killer to work so much better. I had tried a couple others including noOTA but there was always some notice that an update was available. At least an annoying gray 1 badge in the settings.app. This one completely removed any sign that there's an update available. Now my OCD is much better.