Fast Five will be the year's highest-grossing movie by the end of next weekend, but it has plenty of competition in the weeks to come, since this summer-movie season is jam-packed with sequels and expensive would-be blockbusters. So we put it to you: When all is said and done, which 2011 summer movie will be the biggest box-office hit? Pirates of the Caribbean and Transformers both have an amazing track record, but can their latest movies come out on top in such a crowded summer? And then there's the last Harry Potter film, which is poised to score big even if last year's Potter installment was only the fifth biggest film of the year, coming in well over $100 million behind summer champ Toy Story 3 (a precedent that might bode well for Pixar's 2011 sequel, Cars 2). Give us your prediction, and don't forget about all the potential dark horses!