It almost seems that we're to a point where we just have to accept this as an industry. The frequency of outright copies seems to be increasing, and there's not much the Apples of the world can do about it. Seems like this is common place on the web too, where various design memes (the ribbon thing, etc. etc.) eventually spread to a large number of sites. Given that Apple is still making boatloads of cash, it seems like this isn't reducing their incentive to innovate.

(Not that I'm endorsing what seems to be an outright copy)