I played the game at Expo and definitely liked it. It set's the mood for the theme very well. I think the rules already have aspects that will be very good when finished. IMO the rules could make this an A game. It's definitely challenging, with some tight shots and can be a drain monster. The ramps are very cool, the way the ball goes behind the back panel and back on the opposite side seems cooler than on other games with a similar setup. I think it's because of the length of "disappearing" time.
I'm glad it's not a straight up fan layout (more of a modified fan), as there are getting to be too many. My one concern about TBL is that it's a 100% tried and true fan layout. It's a great layout for most people, but I've already got quite a few of those and I like something a bit different - although there is more risk for the designer that a non-fan might not play as well.
The majority of people really disliked Iron Man at first (including me) because it's tough. But now a majority like it, because of good rules and the challenge. Excellent rules, challenging shots, and a well integrated theme (voice callouts pending) = could be great. We just need to wait on the rules.