Wireless XBOX gaming works a treat!
There should not be any difference in wireless speed to that of normal routered or direct
XBOX connections; just avoid ICS (Internet Connection Sharing) through MS Windows, that will slow you down.
In addition to your Wireless router you will need a wireless Bridge, which makes your XBOX wireless. The Linksys Wireless bridge of choice is the
Linksys WET11.
There's a guide going to be released in the
XBOX Useful Information forum shortly.