I'm actually quite amazed that the 360 has sold so well during these holidays. I gotta admit, I was one of the people saying the PS3 would outsell the 360 for the year, but I was wrong.
My guesses are that once holidays die down, the PS3 will continue to outsell the 360 for the most part of 2012. During that time, the PS3 will close the gap with the 360 up until the holidays, which will most likely be the scenario as these holidays. Also, if a new xbox is announced during 2012, I will assume that the 360's sales will slow down a bit, then again MS did say that Kinect would add 5 years to the 360's lifespan...This gen is confusing :/