I think you can get a really good deal on one right now. Dealers usually have around a 7-10% mark-up on these rigs, and there are quite a few of them sitting around. My local dealer ran a locator on 2003 white only Denali's and came up with 6 of them!
And we live in the middle of nowhere. I traded a 01 Denali for this new one, so I don't know about outright deals, but it is a buyers market. You will LOVE the 03, they have a new dash and features that make it a GREAT vehicle to drive.