When Lucas had kids, he decided "Star Wars" was a kids movie. That how we ended up with the Ewoks and Jar Jar Binks. Maybe he's finally realizing that, even though kids may like the movies, it's not a "kids movie".
I don't have a problem with the PG-13 rating for SW. (Although I thought it was stupid when they came up with the rating after "Temple of Doom" -- parents ought to be aware of what movies their children are seeing and what they're about without relying on a set of judges to tell them what's appropriate.)