The USA's Federal Communications Commission (FCC) has apparently approved the wireless controller for the Xbox 360. If you really want to geek-out, you can see the details, which were posted yesterday,
here.
There's really no mystery about whether this is the 360 802.11n WiFi adapter - it says so on the label that you can see pictured in this story.
What might be more of a shock is a price suggested by
Xboxfreedom, which states, "The word out there is that since the new adapter has two antennas as opposed to one in the old one, it will be priced at not less than $200..."
We're finding out the actual factuals on that price.