I'm not expecting to see any updates so soon... Bought a MacBook just after they were updated to the Core 2 Duo and I know for a fact that there is no new Intel hardware comming down the pipe for some months. About the only thing Apple could do is to drop the price a little if they wanted to stimulate the post-Xmas market some. If the sales figures end up anything like I think they will for the (MacBook at least) I think demand is still going to be too high for Apple to be tempted.
As has been pointed out it is only two weeks though - so if you can, wait (and probably get iLive 07 with the machine as a bonus).