A few tidbits from the
TV Guide Interview are below. Sounds like they really want to get to 100 episodes... probably so it can stay in syndications after it's run is over.

TV Guide: What about your Star Wars live-action series for TV?
Lucas: Yes, I'm working on that. We're just going to start writing it in about a month from now, start doing scripts for it.
TV Guide: And where will that live in the Star Wars continuum relative to Clone Wars and relative to the films?
Lucas: Well, Clone Wars has got all the characters in it — Yoda and Anakin and Obi Wan and the Emperor and all that — so it's basically the movie.
The live-action [series] is not the movie. It's the Star Wars universe, but it's characters from the saga who were [previously] minor, and it follows their stories. It's set between [movie episodes] III and IV, when the Empire has taken over. It's like Episode IV in that the Emperor and Darth Vader are heard about — people talk about them — but you never see them because it doesn't take place where they actually are. There are storm troopers and all that, but there are no Jedis. It's different, but I think it's very exciting because I get to explore a part of that universe that I haven't been able to explore. Once you have a saga, it's got a lot of requirements because it's about a particular [thing] — in this case, Darth Vader — and so it's his story from the time he's 10 to the time he died. You really can't go off that track because that's the story. Whereas now, I can make a left turn on 10th Street and go down there and see what's going on. TV Guide: And how are you going to produce this one? Are you going to film a certain number? Are you going to have a deal with a network before you go ahead with filming?
Lucas: No, we'll do it just the same way that we're doing the animated series, which is we usually write a whole year first, and then we'll start shooting, and then we'll shoot the whole year and then once we've got [something to show], we'll see where we can put it. We're going to do a hundred of them, too. [It should be] easier [to place] than the animated one because it's live-action.
TV Guide: So you'll film before you get a commitment? Or how will that work?
Lucas: Well, we're doing these before we get a commitment, so we're just doing them on the faith that we're going to [sell them]. I mean, we're doing them ourselves, so we can finance them, we don't need to have a commitment of any kind. We're simply going to sell them.