Diablo 3's most recent delay—from "late 2011" to "early 2012"—shouldn't come as a surprise. The third entry in Blizzard's classic series has been in development since shortly after the turn of the century, after all.
The earliest version, developed by the now-defunct Blizzard North, was completely scrapped in 2005, and a from-scratch new version's been in the works since. But the public beta's still going strong, so there's no doubt the game will definitely come out soon.
And besides, worrywarts—not every game stuck in development purgatory stays there. Whether your most looked forward to game is Shenmue 3 or the next Half-Life, you might take comfort from our list of delayed games that actually hit shelves. Of course, whether or not they were actually worth the wait is a different issue.