Ja, apparently it's an Xbox 360 and it has USB ports.
However, my USB WiFi dongle came with software/drivers that had to be loaded - the default Windows stuff didn't work (but was fine with the PCMCIA card). I dunno if the Xbox would need software/drivers, or if there's a way to load 'em.
I can't see, otherwise, why the Xbox WiFi thingy is so expensive.