MovieBob said:
Anyone who hasn't seen both is going to be completely lost.
While the whole big movie continuinty thing is fairly cool, I think this is going to become a big problem. By far the biggest issue comics have is that they're almost completely incomprehensible to anyone who hasn't been following them for a long time. So many different characters, worlds, plot arcs, and so on constantly being introduced, killed off, retconned, rewritten entirely, and so on, makes it incredibly difficult for new readers to actually find a place to jump in and start reading.
And now we're starting to see exactly the same thing happen with the movies. It's not too bad so far, since there aren't too many films and most people interseted in the new one will have at least had the chance to see the previous ones. But what happens in 10 years time when there are twice as many films, all even more reliant on what has happened in earlier ones? What happens if DC ever get their shit together and suddenly there are two series of films that you can't miss seeing any of, but still need to keep separate? What happens when people who aren't even old enough to be watching them now want to get involved, but don't want to work through a decade's back catalogue of dated action films?
Having movies set in the same universe, with crossovers and cameos and so on, is one thing. But if the audience needs to follow a whole series of films just so they're able to understand what's happening in what is ostensibly a stand-alone solo film is likely to become a problem.