http://www.imdb.com/title/tt0367882/

Now that Karen Allen's signed on to repirse Marion Ravenwood (and she looks scarily good so I'm guessing she's had a LOT of surgery) I'm getting a bit more excited about this.

I mean, Die Hard 4.0 wasn't a massive pile of arse. Indy 4 might actually work.

Lucasfilm have apparently registered the following titles:
Indiana Jones and the Destroyer of Worlds
Indiana Jones and the Fourth Corner of the Earth
Indiana Jones and the Kingdom of the Crystal Skull
Indiana Jones and the Lost City of Gold
Indiana Jones and the Quest for the Covenant