This probably doesn't matter to most people, but what I found interesting about the One X is that the lock button is in a place where you hand naturally rests when you pick up the phone with one hand....Whereas on most phones when you hold it in one hand you have to reach over the curve in the top of the phone to reach it and it's really awkward...
Besides that, though, HTC has some really innovative stuff in their new line. Capture video and take pictures at the same time. A majorly lighter interface. You should check out the HTC One X page on HTC's site for more info.
TBH, Android is obviously the best OS out there. There's a lot more competition in the Android phone market, which means that companies are constantly trying to top other companies and make their products better and better. Everything you want on the iPhone, the Android can do too. Dual core, voice commands, 8MP camera, social networking, plus a lot of stuff the iPhone CAN'T do like widgets, 4G speeds, keyboard and OS flexibility, and bigger screens. Obviously iPhones have better app selection, but that's just because Apple people have a lot better dev tools. If you want a phone you can pick up and start using immediately, though, you should probably pick iPhone. Android is better, but it takes a bit of figuring out.
Anyways, good luck on your search, I hope I've helped a little!