Not sure if this is old news or not but anyways..
I wanted the wireless adapter so I can have the 360 in the bacement but didn't want to fork out $130 for the wireless adapter.
I bought another wireless router for the 360 and configured it for bridge mode. Now the router is basically a wireless hub that talks to my other wireless router and the 360 just connects to it via its ethernet cable connection. The router only cost me $30.
Hope this helps someone.