Although it didn’t quite make the lofty $150 million projections of some irrationally exuberant analysts, Iron Man 2 got the summer movie season off to a sizzling start as the heavy metal sequel earned an estimated $133.6 million.  The Jon Favreau-helmed film scored the 5th biggest box office opening ever (in dollars), though if ticket price inflation is taken into account, it would drop to 9th.

Unlike 2010’s other heavyweight releases Iron Man 2 was not shot or released in 3D, though it did gain about 8% of its total from pricy IMAX venues.  Paramount opened Iron Man 2 in 4,380 theaters (and nearly 10,000 screens) making this the widest debut ever, and Old Shellhead’s new saga managed to score an extremely impressive $30,502 per venue.  Iron Man’s debut set a new record for Paramount releases, and was the second best May bow ever, trailing only Spider-Man 3, which opened with $151.1 million.

Iron Man 2’s opening was 31% better than that of the original Iron Man film, which garnered $102.1 million (including Thursday night shows) in May of 2008.  The sequel was aided by a wider release (7% more theaters), higher ticket prices, and 181 IMAX theaters, where IM2 set a new record for a 2-D film’s debut.  Iron Man 2 totally dominated the U.S. box office this weekend, earning 78% of all the cash brought in by the top ten films.

Overseas the film remained dominant in its second weekend, earning an estimated $57.2 million and bringing its non-US cumulative to $194 million.  Given that the film has already earned $327.6 million, it appears more than likely that IM2 will surpass the first Iron Man’s worldwide total of $582 million, and it could do much better in the unlikely event that it can match the incredible “legs” that the original film displayed.  Given this auspicious debut, there is little doubt that Marvel will return Favreau & Company for a third film.

Iron Man 2 did post an 11% drop from Friday to Saturday night, and will likely see a fairly steep percentage decline in the weeks ahead.  Still audiences appeared to love the film, giving it an “A” CinemaScore.  Film critics were more circumspect in their praise, but reviews were still generally positive.  According to Paramount 60% of the audience during the opening weekend was male and 60% was over 25, which might actually be a good sign for the film, since Iron Man is (as superhero films go) a fairly “female-friendly” franchise, and school-bound younger viewers should have more opportunity to see the film over the coming weeks.

Last week’s chart topper, A Nightmare on Elm Street, took it on the chin, falling a precipitous 72%, but still brought in an estimated $9.2 million.  In contrast Dreamworks’ 3D animated feature How to Train Your Dragon, which didn’t have to compete for the same movie-going demographic, fell just 36% as it earned $6.8 million and brought its cumulative past the $200 million mark. 

The Tina Fey/Steve Carrell comedy Date Night fell only 30% in its fifth frame.  Date Night earned $5.3 million and brought its domestic total to $80.9 million.  It has the kind of staying power that might make it possible to slip past the $100 million mark, no mean feat these days for a film that opened with just $25 million.

Like Nightmare, the Vertigo comic-based The Losers had the air sucked out of its balloon, dropping $69.4% as it added a mere $1.8 million in its third frame.  With just $21.4 million in its coffers so far, a $25 million finish appears likely.  Lionsgate’s Kick-Ass, which is based on the Mark Millar, John Romita, Jr. comic, also took a heavy hit, tumbling 66.6% as it slipped out of the top ten in its fourth weekend.  However Kick-Ass, which has earned over $45 million domestically, has made a total $75 million worldwide and stands to do well on DVD--and the Kick-Ass graphic novel remains perched atop the bookstore GN sales charts.

Compared with last year when the revamped Star Trek opened to $75.2, the weekend box office total was up 23%.