My iPhone 3G has been experiencing problems before I upgraded to the second to newest OS, which didn't really make a big difference either way. Prior I had wiped the phone and did a fresh install, but still it would operate a bit clunky. In a nutshell, most of the time it's very slow to sometimes completely non-responsive to my touch. I am somewhat indecisive about getting the new iPhone due to the antenna issue and rumors that possibly Verizon might get an iPhone, as I am not too keen to sign a two year contract with AT&T again, plus rumors about an iPhone 5 around the corner...