It's true that I think some of your list will flop hard, but to base longing/shorting on what the hype is this far out (for some) is not a great tactic. I have been taking notes lately and I found that in the last month or less before a movie comes out, the advertising begins. (I believe)it all depends on the budget for advertising. Analysis would suggest that if the budget is big, it would pay for more spots and an earlier start of the campaign. If the budget is low (and/or it's a low budget movie), it seems that there are only 1-2 weeks of sparce advertising. I find it more accurate to monitor movie related sites (as you suggest) and base my longs/shorts on that.
Tron, for example, is starting to get some hype and I am starting to see advertisements. I didn't think it was going to do well a month ago, but now I think it will. On the other hand, Yogi has started advertising and it has fortified my opinion on it's general suckiness.
Anyway, the bottom line here is, do your research and you shall prosper. Longing or shorting everything is a weak strategy and will never result in maximization of your investments. Informed investing is always more lucrative.