I was under that impression too. However, the 29th has also been rumored as the day. Who knows.
My money is on the 22nd, as AMD just released their price cuts this Monday. The 22nd would make more sense.
One thing's for sure, I think the level of activity will die down in the Mac Pro forum when it gets updated and all of us "waiters" buy it. (Except for MM - he's waiting for SS 🙂 )