From the announcements from CMs, here's what I determined you can and cannot video or photograph at
Disneyland and DCA...
DCA:
Soarin' Over California: No flash photography or videotaping while on the ride
TOT: No photography or videotaping of any kind (not even non-flash photography) while in the elevator
Muppetvision: No videotaping or flash photography
It's Tough to Be a Bug: No videotaping or flash photography
Aladdin: No flash photography or external video lighting
Also...no flash photography or external video lighting on any attraction
Disneyland:
No flash photography or external video lighting on any indoor attraction
No flash photograhpy or external video lighting on the railroad train ride during the Grand Canyon and Primeval World scenes
You can take photos and video on California Screamin', Splash Mountain, Big Thunder Mountain, and any fast ride. I've taken video on California Screamin' many times and no one has told me to put away the videocamera. Make sure you hold on tight to your cameras and camcorders or they will fly into orbit!
Generally, a CM will make a loud and clear annoucement that no videotaping, external video lighting, and/or flash photography will not be permitted in the attraction. If in doubt, ask.
A few indoor attractions are hard to videotape because of low lighting. I tried to videotape the Indiana Jones ride and 90% of the video was all black.
I've taken video on Goliath at Six Flags Magic Mountain, if you can believe that, and I've managed to hold onto the videocamera nicely on that roller coaster.