None of the US networks are even close to maximizing the speed possible with 3G and 3.5G technology, I'm not sure I'm going to hold my breath for LTE.

There would be no purpose in deploying LTE on a phone this summer. While it might be available in pockets of the US, it's not going to be widespread internationally. Most of the Android phones that come out with support for it will be all but abandoned in 4 to 7 months after release.

I'd say iPhone 6 (summer 2012) at the very earliest. At this point I can't see them unleashing anything in iPhone 5 that would make me switch from my iPhone 4. Unless of course I can sell it (it's factory unlocked and works everywhere) and upgrade for next to no money, pretty much in prep for the following year's upgrade.