Once DVDs are sold, The Dark Knight will have made just short of a bazillion dollars. So, I imagine the pressure is on to use the better known villains and even better known actors for a sequel. But I hope Nolan resists the urge, and he may. This is the guy who relaunched the franchise on the backs of Ra's al Ghul and the Scarecrow.
Heh - the next film surprising us is one thing I'm not worried about.
I don't think it's about better known actors so much as good actors. Luckily there are many good actors who are well known, and so far the execs who are running the Batman franchise and Nolan have done just fine balancing those two aspects. I mean, it's not like Phillip Seymour Hoffman is a giant box office draw. How many people here saw The Savages? But Johnny Depp is, while still being highly skilled. It would be a good mix, though as many say it's just rumors. What's been interesting about the rumors so far in the history of these movies is that the villains are usually right (we heard about Scarecrow and Ra's pretty early on, and Joker too) and the actors are often wrong, because the rumors are generated either by the actors themselves (or at least their agents) making bids for the parts or just looking to up their media cache, or by fans who'd like to see so-and-so in such-and-such part. The one reason to not dismiss completely the actor business is that the very earliest rumors were fan-generated... and turned out to be right. Not only was Christian Bale cast, but he's been amazing in the part.
See, we're not always just wanking ourselves. Only part of the ti... well, maybe 50% of the... okay, most
of them time - but not always.