Just to let people know, I applied early and went complete, according to them, on 9/25. They only started to review apps around mid to late December (talked to a rep visiting my college), and I managed to only get a decision back several days ago.
On the status checker, I went to Decision Mailed around 12/28 or so (although it read "Updated on 1/1/07"). So, take the "4-6 weeks" notice with a grain of salt. However, you should receive a letter in 7-10 business days once it goes to Decision Mailed.