Update 02/12/06:
Xbox 360 available in the I4U Shop Again!

Update 01/14/06:
Amazon and Wal-mart have Xbox 360 Bundles in Stock again

Looks like the second wave of Xbox 360 consoles are at the retailers. GameStop has two new (expensive) Xbox 360 bundles available to order, which ship within 24 hours.

The GameStop Xbox 360 Titanium Bundle sells for $1,499.77.
The bundle contains Xbox 360 Premium Pack, 15 games, Universal Media Remote, Wireless Controller (maybe 2 or it is typo), 2 Game Guides and Xbox 360 Skin Gels.

The GameStop Xbox 360 Steel Bundle sells for $999.86.
This bundle contains the Xbox 360 Premium Pack, 7 games, extra wireless controller, 2 Game guides and Xbox 360 Skin gels.

Visit GameStop for more details.
Update 12/15/05:
They Xbox 360 bundles out of stock again. Shipping date is now 31th of January 2006 on Gamestop.
I mean this is the last couple days before X-mas. And it has now been a couple weeks since the Xbox 360 launch in the United States. New Xbox 360 should be in stock again. I am not sure if there will be unbundled Xbox 360 for the standard price available. Retailers want to squeeze the most out of the Xbox 360 shortage and hype and bundles are just a great way to enhance the margins.

Also check eBay for Xbox 360 offers.