Works fine on mine! Just downloaded it Friday night.
We have two 3 month old 4s and it seems great. My only ***** is that the swipe up to open the Control Center takes about five attempts and it doesn't even work on the lock screen like it is supposed to.
Thanks guys. I've had it on my devices for a few days now and the only real complaint I had was with the battery life. I turned off some settings as recommended in MrJarrell's post above and it has seemed to help.