This is true.
I just bought Rob's book and a WET11. I cracked it open and there is not a separate radio card.
Everything is on a single circuit board. I hear you can tell the difference between the two WET11s by the logo. The new ones (mine included) have a cisco logo on them as well as a linksys logo.
Incidentlly, there are only two screws holding the cover on. I you're looking at the bottom with the logo up, the screws are on the upper left and lower right under the rubber feet.