My local Wal-Mart has the xbox 360 out on display. Well it is behind glass and you can't play it. No games are in sight. And the 360 was in preview mode. But it was my first time to see it in person. I also believe they had the wired controller hooked up to it. I guess they have not figured out what to do with the wireless controller yet.
Uupdate: Here are some pictures of the xbox 360 at a EB Games Store. My Wal-Mart does not have anything like these setup. Ours was behind glass where they sell the games and there was one controller.