johnsobas, I believe this is what the PS2 looked like when the slim launched:
http://vgchartz.com/hwcomps.php?cons1=GC®1=Japan&cons2=PS2®2=Japan&cons3=XB®3=------&start=38256&end=38382
It shot up to 131k, which is pretty close to Christmas level (about 360% increase YoY). I'm quite sure it didn't come with a price cut, either, which would have easily put it above the PS3 slim launch.
I don't think we can make an exception for the PS3 that it's "the only console that has ever done this," just because it was selling like crap last year. The 360 has had many software boosts larger than its Christmas boosts, and if we're talking YoY boosts, there's at least one as big as the PS3's.
For example, the week of 9/16/07 it sold 1.5k, but on week 9/14/08 (IU release) it sold 28k.
