I considered going to this yesterday. I hadn't heard much about it (don't have tv) but very rarely has George Clooney disappointed me in a performance.
I have a hard time deciding on the actual target audience. A lot of the movie is grounded in the forward-thinking ideals of the Worlds Fair and Disney. It's not an easy concept to explain to kids, but at the same time, it's how kids think. It didn't start off very good (some playful banter schtick between Clooney and Robertson that had me rolling my eyes) but it got better once it got passed that.