This is not exactly news, more of a FYI that I wanted to share with others who may be interested. The Panasonic Viera PZ850 (the one with YouTube, Picasa, and Amazon VOD) works with the original Xbox Wireless-G Adapter and may work with other wireless adapters.
I wanted to test out the online features but I didn't have a CAT5 long enough so I hooked up my old Xbox Wireless-G Adapter "just to see." Sure enough, it connected without any problems at all and has been streaming content ever since. I haven't had any issues dropping signal, granted, I am only a couple of rooms away from the router.
Just putting this out there for those with a new TV and an old Xbox Wireless-G Adapter. I wonder how many other wireless adapters work with newer online-enabled TV's?