I installed iOS 7 GM today on my iphone. It's certainly pretty to look at. I find it smooth enough to where if I never used iOS 6 I wouldn't be the wiser. However, iOS 7 is not as smooth as iOS 6. While it is very close, most animations when dissected and looked at closely are not as fluid as iOS 6. I'd like to point out that this isn't necessarily my opinion or bias but facts. For most people it won't be an issue and they will be happy to enjoy all of the nice new eye candy and features of iOS 7 but I just wanted to point this out.