I tend to glance at the Convention and Tourism postings :
http://www.lasvegastourism.com/conventions_oct.htm
Agree that some of the major, annual events, such as NFR, CES, EDC, WSOP really push UP room prices and also push UP +EV for decent poker players. IN addition, one can look for some major corporate events as +EV for specific parts of the strip.
Example: Amazon Web Services has a 55,000 person presence at Venetian Dec. 2-6. Certainly, this will add a certain amount of newbie players to the poker room during that time.