I'm looking at replacing a 2.5ghz quadcore G5 with a 27" iMac. I am debating between the i5 and the i7 mainly. I am just wondering what how much a performance difference over the G5 there will be, and if the i7 is really worth the extra $. Price isn't a huge issue, but value is. I am leaning towards the i7 as of right now. The computer won't have heavy use, but will occasionally be used with some decent size FCP projects. Does anyone have any input on the G5 versus the i7?