I'm loving it so far, and that's coming from a former iPhone4 owner. Not a single glitch, large, bright screen with great angle viewing and contrast and just the right size for my hand and pocket. The battery life has been way better than expected so far, but maybe it's because I don't use the GPS (off) and I'm not in a 4G area which are probably the biggest battery drains.
My wife also came from the IP4 and loved that phone along with her iPad. She's been impressed so far, only negatives I've heard from her so far is she liked the easy flip switch on the iPhone to mute that this doesn't have and a couple of apps that Android doesn't have that Apple did. She's still getting used to the apps and widgets and I'm sure she'll like it even more once she does.