We all went today, me the wife and the two kids (Girl 7, boy 3) and we all enjoyed it. Its as good as you want it to be if you approach it with an open mind. If you convince yourself it will be shit before you go, then, just like the new Wembley, it will be shit when you get there. Like somebody said earlier, its only a cartoon, and some folks are taking it entirely too seriously.
By the way, I thought the new Wembley was ok, nothing massively stunning, but decent enough all the same. Just like the Simpsons movie really, isn't it funny how things in life mirror each other.
I don't know, perhaps I'm too easily pleased.