Don't worry, no one is pitching Christoph Waltz AS Tarzan, that part is going to Alexander Skarsgard, the blonde one from True Blood...the asshole from the Straw Dogs remake? You know, the guy who looks like a nordic Tarzan? He's gonna be Tarzan.
Warner Brothers wants Waltz to play an army guy or something, it's unclear right now, but they know Christoph Waltz is going to be bad news for Alexander Skarsgard and probably a bunch of gorillas too. And maybe the forest. NOT THE FOREST, WALTZ!
David Yates is on board and this is being treated as an adaptation interpretation of the Edgar Rice Burroughs novel, not a remake of a previous Tarzan film, of which there are many. There have been a few writers who have taken a crack at the script and we'll see which three get the credit when and if the movie gets green lit.
The go-ahead is expected to be given sometime in November so production can start next summer, but they're already trying to rope in a cast, so I imagine they're confident this is happening. Yates has even been meeting with actresses to play Jane. I will also meet with any actresses that want to play Jane.