The overall design of the cave is almost identical of the cave of Batman Begins, with it being a basic cave without cavernous drops.
The waterfall is still there.
There have been upgrades with better lighting than the basic generator powered ones put up in Batman Begins.
There is a whole new batcomputer similar to the set up in The Dark Knight.
There is a weapons area where all of Batman's equipment used in both films, plus new gadgets, can be seen.
There is also a cabinet containing both Batsuits.
The cave isn't featured much in the film, it is has about as much screen time as the previous movies.
The Dark Knight Rises hits theaters July 20th, 2012 and is directed by Christopher Nolan starring Christian Bale as Batman, Tom Hardy as Bane, Anne Hathaway as Selina Kyle/Catwoman, Gary Oldman as Commissioner Gordon, Morgan Freeman as Lucius Fox, Michael Cain as Alfred, Juno Temple and Josh Pence as a young Ra's al Ghul.