A check of Best Buy.com, Circuit City.com, Amazon.com. and Gamestop.com revealed 360 is still apparently having supply issues. In many cases one or more SKU was not available.
At Amazon, the Elite is currently not in stock but only available from resellers.
At Gamestop, only the pro is available for online order, but checking store availability (put in your zip code and 100 mile radius) revealed virtually all models appear to be completely sold out at brick and mortar locations.
At Best Buy the Elite is sold out as well. Pro and Arcade are available online, but store pickup is not an option for Pro and Elite, an indication I would think of tight supply.
Circuit City was sold out of Pro online, I didn't check other models.
This is an online check only, I haven't been to brick and mortars lately.
It is pretty impressive (or bad for MS manufactoring department) that 360 is still experiencing some shortages on Jan 21.