The winner of the 3-day Fourth of July weekend box office derby won’t be known until final figures are in on Monday as two heavyweight sequels slugged it out in a battle for big screen supremacy.  Both Fox’s Ice Age: Dawn of the Dinosaurs and Paramount’s Transformers: Revenge of the Fallen were estimated to have earned $42.5 million, though Ice Age, which opened on Wednesday, has the edge over the 5-day period, $67.5 million to $65 million because of stronger performances on Wednesday and Thursday.  Michael Mann’s Public Enemies, which stars Johnny Depp as John Dillinger, earned an estimated $26.2 million over the weekend, finishing in third place and helping lift the total box office 2% over the same frame last year, when Will Smith’s Hancock debuted with $62.6 million.

Weekend Box Office (Studio Estimates): July 3-5, 2009

In spite of higher ticket prices and extra coin earned from the widest 3-D launch in history, Ice Age: Dawn of the Dinosaurs (which should definitely win the Oscar for “Most Unscientific Title of the Year") took five days to earn what its predecessor, Ice Age: The Meltdown, took home in just three days in 2006.  Of course Ice Age: The Meltdown didn’t have to face competition from a blockbuster like Transformers: Revenge of the Fallen, so it’s important not to sell the third Ice Age film short.  This is especially true when considering the fact that Ice Age: Dawn of the Dinosaurs managed to post the sixth best international opening ever with an overseas total of $148 million (the best ever extraterritorial debut for an animated film).  The new Ice Age film played on 1,606 3-D screens here in the U.S., and on 2,126 in the rest of the world, where the 3-D locations, which represented just 18% of the total screens, accounted for 54% of the film’s take.  With numbers like these, the 3-D boom is clearly not going away anytime soon.

Transformers: Revenge of the Fallen fell a whopping 61% from its opening weekend, but when a film opens that big, a precipitous drop is unavoidable.  More important is the fact that the film sprinted past Pixar’s Up to become the #1 movie of the year so far with a cumulative total of $293.5 million.  On Monday or Tuesday Transformers will become the first 2009 film to pass $300 million, and it should end up north of $400 million, though it has now fallen well behind the pace of The Dark Knight, which had brought in $334 million during its first 12 days of release.

Public Enemies, which played to an older, male (53%) audience, debuted strongly with $41 million over 5 days.  While 65% of the reviews on Rotten Tomatoes were positive, the film did receive some brickbats from high profile critics, and with a mediocre CinemaScore of “B” from those who attended, word of mouth may be tepid.  Still, the film has given the long dormant gangster genre some much needed life, and Depp’s stylish performance could keep this film in the top ten through the end of July.

When faced with an onslaught of blockbuster tentpoles, comedy still remains Hollywood’s most potent counter-programming gambit, and both The Proposal ($12.8 million) and The Hangover ($10.4 million) continued their stronger-than-predicted summer runs.

Despite the loss of its remaining 3-D screens to, and direct competition from Ice Age, Pixar’s Up remained solidly in the top ten for the sixth straight week, earning $6.6 million and bringing its cumulative to $264.8 million.  Up is now the second biggest domestic hit ever for Pixar, trailing only Finding Nemo’s $339.7 million.  While it won’t catch Nemo, Up does have a chance to pass the $300 million mark