Seems like a pretty cheesy "fix", if they released a defective product they should fix it, recall it, I'll skip the the iphone4 and the free bumper and just wait for the iPhone 5, you shouldn't need to buy a bumper because they were too lazy and greedy to do proper testing, hopefully they don't mess it up on the iphone 5
Apparently Steve Jobs's best engineers told him about the defect in the design but he failed to act on it. I heard they are going to give out free bumpers to iPhone customers but IDK.