It's kinda funny actually.
Prior to the Kinect bundles the 360 was the cheapest option at $199 (before the Wii price drop) and a lot of Sony fans said that the more expensive console was selling just as well. But now when you factor in people buying Arcades with the Kinect ($300) and the expensive 250gig with Kinect ($400) I'd say the playing field is more even, and that Microsoft is doing better as the higher priced console - especially when you factor in $60 a year for live and people buying hard drives for their arcades ($130 MSRP) and some wireless adaptors for the old units ($100).
Microsoft has the advantage here over the PS3. Not the other way around.
It's just that simple.