Batman is probably the prime example of this. Announcing games before they are even close to being released. This past E3 was better than the last ones concerning games that were just teased. Personally i would like more of something in the line of what EA did. Showing concept art and letting the developers speak about the game.
Arkham, Bioshock, Watch Dogs, etc all get announced years ahead and even get delayed. If you're not ready to show the game, then you shouldn't announce it. Games are awesome, but publishers feed us with teasers, trailers and controlled gameplay demo's way before the game is ready. We're not babies that need to be spoonfed this. We want the real deal and see how the game plays, not how it looks with a CGI trailer.
Microsoft did this the most with games like Scalebound and Crackdown, but others did this aswell don't get me wrong. But i don't get excited with something that doesn't show anything.