If you haven't already, look at the i7 950... It's $30 more, BUT... when you're checking out you can see the box for promo codes, right? Click the link right next to that, scroll down, and there's a $20 off promo for the 950. Meaning you pay $10 more for an extra 200 MHz or so. (whatever the gain is, $10 isn't bad)
Just did that last night for my order, saw your post and wanted to suggest it.