Birds... Fast Birds... Focus Help Needed w/7D 70-200 f2.8 USM IS II

You can also try trap triggering. That's going to require using custom firmware, a lot of planning, and a ton of luck, but I know that with Magic Lantern you can set it up to trap trigger. Which for things like humming birds is quite useful, but for other types of birds it's going to be a lot more hit and miss.