It's interesting, but for me to jump ship from my S3 I want the hardware & software to be interesting. The iPhone 5/5S doesn't do it for me and iOS 7 will have some really annoying bug in it and maybe it will suck compared to iOS 5 (last one I used) So iPhone 6/iOS 8 will be the litmus test for me.
I love the Nokia 920 and Windows mobile is interesting. But I hate AT&T and am with Verizon. The 928 is kind of bland.
But to be honest, a new phone release doesn't have the same WOW factor it used to have- like with the early iPhones, the G1, Droid, Nexus, the early HTC phones, etc. Back then, I would go out and pay extra to get the newer phone. Now I feel like the next phone is slightly faster, bigger, with a better resolution screen and the OS has some features that really aren't necessary that aren't interesting to me. Remember when you used Google maps for the first time? With GPS? That was, and still is seriously amazing and useful. Smart scroll? Not so much. Surfing the web, open table, etc. All really useful things. Flat design? Another Android skin?
Ehh... I'll wait for my 2yr upgrade. I am perfectly content with my S3.