Bashiok: There have been a few discussions about chests, what they meant in the previous game, and what they'll mean in Diablo III. Currently there are no locked chests, and it's not something we're looking to reintroduce for now. We have discussed varying chest quality and types, adding randomness not only to the appearance of a chest but also the value of items it may drop or possibly specifically what types of items it's guaranteed to drop. Mix it up a bit and make finding a chest exciting, but make finding a special chest something even rarer and more exciting. It could certainly make exploring the entire floor of a dungeon more compelling before moving on.
The fact that there will be higher qualities chests is very interesting, it remind me of the SNES games Lufia 2 in the ancient cave where there was blue chest that contained very good equipement, in fact this system is one of the reason why I go back to play this games every 8 month.
I liked the idea of locked chests.
@Murderface: loved your idea, get to the surface through hordes of monsters!!