I just caught the Opening Monologue from WWDC. It's pretty funny. Apple is so great at marketing. Marketing alone will get you started but you won't go anywhere if that's all you have. Combine great marketing with the kind of tireless innovation and level of quality they've become known for (e.g. the cooling fan in the redesigned MacBook Pro at 3:20 in on the video) and you get $574.80/share (incidentally, Google is at $564.87).