Interesting tidbit of information I just found out: single lines can get an annual upgrade if they're on a plan of at least $50. The base plan itself has to be $50, not a combination of all the features, but all you have to do is either be on at least the 900 minute plan, or be on the 450 plan with unlimited texting.
So there's no reason to ever do a 1 year contract if you're a single line on one of those plans- you get 2 year pricing on a phone, but a new phone every year..
Something to consider for everyone who's getting an X.. 2 Ghz Gingerbread LTE phone anyone??