Well, the i7 is more efficient clock for clock, so even in single-threaded apps it should be faster even if both were at 4GHz, but the main benefit is the hyperthreading. Whether you'd use that is doubtful, considering most games don't utilise hyperthreading and its main benefit is in encoding etc..
Whether the performance difference of the i7 is worth the extra dosh to the AMD alternative is something worth asking yourself. If you just want "the better one", the i7 is still the way to go. As far as upgradeability, AMD still have cpus expected to use the AM3 platform (eg bulldozer), which gives them some futureproof value, whereas socket 1366 we know will be EOL quite soon. Chances are, by the time you'd need to upgrade an i7 (say 3 or 4 years), AMD would probably be moving onto a new socket themselves. I'd stick with the i7, as I'm a believer in the "buy what's best now or you'll be waiting forever for the next best thing" motto.
Whether the performance difference of the i7 is worth the extra dosh to the AMD alternative is something worth asking yourself. If you just want "the better one", the i7 is still the way to go. As far as upgradeability, AMD still have cpus expected to use the AM3 platform (eg bulldozer), which gives them some futureproof value, whereas socket 1366 we know will be EOL quite soon. Chances are, by the time you'd need to upgrade an i7 (say 3 or 4 years), AMD would probably be moving onto a new socket themselves. I'd stick with the i7, as I'm a believer in the "buy what's best now or you'll be waiting forever for the next best thing" motto.
