I think LTE is going to be a major feature for the iPhone 5.
I can see NFC being a less major feature. Although I don't really need NFC for what it does now, if it's on the iPhone, it will help push the adoption at 10 times the speed it's being adopted now. Right now, only select Android phones have it, and as a result the technology isn't really advancing that quick. With every iPhone shipping with it, that will add an instant boom to the NFC adoption.
That on top of the 4" screen I think is going to be the iPhone 5.
----------
I really despise people who use Google Voice and Skype. I think they are complete garbage services for those of us that have to call people on Google Voice/Skype. It's great for the people actually using it as they save some money, but I have nothing but issues trying to contact my two friends who use Google Voice and Skype. They never pick up their phone when I first call them. Ever. Instead, I have to call them, leave them a voicemail, and hope their notification system decides to let them know they have a voicemail. If you don't leave a voicemail, then forget it... they will never know you called. So anyways, once they find out you called (you know in the middle of the movie that you are at with the rest of your friends who actually responded), they call you back with pitiful call quality and you can barely hear a word they are saying.
So yeah, I'm glad you guys are saving some money by not having very many minutes on your plan. But don't expect me to call you unless I absolutely have to because it's just a nightmare experience.