According to one of Ars Technica's reliable sources, the Xbox 360 lineup will see a marked shift this fall. And the PS3 Slim is still on its way.
This September, the Xbox 360 Pro (60GB, $299) will be replaced by the Elite (120GB, $399). So in one sense, the Xbox will see a price cut. In another, the 360 doesn't necessarily sound like it's getting any cheaper with some lower entry level price.
Also of note, Ars reaffirmed their claim that a PS3 Slim would arrive this fall along with price drops "on the hardware that's out now." Even with these rumors standing as they are, Sony cuts the price of the PS3, it's hard to imagine Microsoft not offering a true price cut as well.