Well as of a few moments ago my three classes at Autodesk University now have over 1000 registered attendees combined.
Here are the three classes I am teaching (The second two are a part of the Powertrack and are being recorded):
CV11-2 Civil 3D® Pipe Networks Made Easy 10:30 am - 12:00 pm Nov. 28
CV23-4 Civil 3D® Corridors: Cul-de-Sacs Are Not a Dead End 1:00 pm - 2:30 pm Nov. 29
CV25-3 Civil 3D® Grading Made Easy 5:00 pm - 6:30 pm Nov. 29
These classes have 275, 287 and 439 in enrollment respectively. That is 1001 students. Amazing.