Sony is putting out a new revision of the hardware. So they stopped shipping for a while to clear out the old inventory. They're making the new ones so that you won't be able to watch BluRays in high def without an HDMI cable.
I bet people bought them up because of the new model. Hoping theyll make a little profit with lines like "OMG RARE PS3, HD USING COMPONENT CABLES!!!" Too bad most people hook up a PS3 with HDMI anyways.
At the store I work at, we're still sitting on a bunch of 120s, 160s, 250s, and the Move Bundles. But I don't think we've had any shipments of PS3s OR 360s in a while.