Earlier this week, Apple told Macworld Magazine (in so many words) that all hardware updates are complete for 2008. "Our holiday line-up is set," said spokesman Bill Evans. There was a rumor of an iMac update, but that's now be squashed. What you see is what you're going to get.
With the recent updates to the laptop and iPod lines (and less recently, the iPhone), the iMac is ripe for a refresh at January's Macworld Expo. The Mac Pro will be ready by January as well, but I don't expect an update to their pro-level machine at a consumer show.
At any rate, Apple's product line is ready for your holiday shopping dollars. Our shopping series of posts will begin soon, so keep an eye out.