Well, it wasn't the first time. They've also cancelled that Warcraft adventure-game where you solve puzzles with Thrall. Seems like Blizzard is going for quality rather than quantity.

I really think it's a pity that they just dump the games though. If you look at Ghost, it does have a look of an alpha-test already. Smooth animation, special moves, prerendered intro, a large number of levels and so forth. I doubt that it'll ever come out for the 7th gen. consoles, but just rust somewhere in the archives.