What's your take on AFROTC drill team competitions? Are they getting more popular, less popular or staying the same? Any idea why?

As a c/Lt.col drill commander i say AF drill meets are getting a little more popular than what they were when I was a freshman basic.
Alot of AF units are starting to mix in with navy, marine, and army units and its working out really well. Maybe Some units would look up to sc-20022 and see that most AF units are the best in the nation.

What would you say are the major drill team competitions in the US for Senior (college & university) ROTC? I'm familiar with Southern California Drill Team Meet (SCIDM) and I understand there is one at the Air Force Academy and there used to be one at Tulane University until Katrina wiped them out. Any others?

They still have the one at Tulane. They just canceled it in 2006 alone. They've held it the past two years though.