I never realized that. One of my apps has it's title in keywords and clearly the Angry Birds apps do too. But I know it often comes down to the luck of which reviewer you get.
Yeah that's one thing that can be annoying. I have an app that does something very similar to at least 15 other apps on the store (that I personally use and think is better than many of the others) that I can't get approved. It was ok 15 other times, but clearly it shouldn't be allowed on the store.
Now my job isn't to fix bugs or add improvements I'd like (as I've already made it do everything I want in my personal use case) but to figure out what I can possibly add to make it acceptable to Apple.