Turns out the batteries were at fault, but by the time I went "Wait, weren't those new batteries from the same pack that died in the TV remote? What if I just got some new ones?" I was too busy riding and having fun. I rode a lot today.
But here is the neat maintenance elevator that we rode to the top of the lift hill:
And here's what part of the ride looks like from halfway up (and then the camera died):
Busch Gardens is a beautiful park and there are lots of great places to take neat pictures of tangled tracks and foliage and trains and stuff. I'll visit them tomorrow with fresh batteries, and write a full trip story later on.