A new set of paperwork showed up on the FCC website yesterday, and it is pretty clearly the Nexus 7 3G.
Asus took the usual precaution of hiding all the important info, including the pictures, user manual, and so on, but they did not think to change the model number. This tablet is listed as the ME370TG, and it took me about 30 seconds to confirm that the current Nexus 7 is the ME370T.
I think this is a good sign that we'll see this tablet at Google's event next week alongside the Nexus 10 and the new Nexus 7 with 32GB of storage. That would certainly fit with some of the rumors going around in the past week. I wasn't sure I believed them, but paperwork always trumps rumor.