Ever since Stephen Spielberg's 'Jaws' burst into theaters back in 1975, Hollywood has viewed summer as blockbuster season. That sweltering stretch from June through September has become the place for big-budget flicks with broad appeal, and the legacy endured to this day. The only real change to the whole "summer blockbuster" paradigm has been that "summer" now apparently starts in April.

Adding an entire extra month (or two) to the schedule has allowed studios to cram in more movies designed to lure bored teenagers and families on vacation into the theater. However, 2011's season is so packed with pictures that some pundits are worrying that this could be the year where box office gridlock has an adverse effect on the bottom line.