Thanks to a HPANA news tip from Nikki Daniel, you can look forward to seeing the first movie trailer for Harry Potter and the Prisoner of Azkaban, right before another Warner Bros. flick released this November 14:
I work for a cinema chain and handle all the trailer requests from the studios. I've been sitting on a rumor for several weeks now. However, it was confirmed today by my Warner Bros. rep that the first Harry Potter and the Prisoner of Azkaban trailer will be on Looney Tunes: Back in Action, which opens Nov. 14.
The Leaky Cauldron reported on this rumor back in July.