If you noticed your "Iron Man 2" screening on Friday wasn't sold out, you weren't the only one.  The highly-anticipated sequel opened to a strong, but not spectacular first day of $52 million.  Historically, that places it seventh all-time behind 2006's $55.8 million for "Pirates of the Caribbean: Dead Man's Chest."  That also makes "The Twilight Saga: New Moon's" $72.7 million single day record safe for quite some time.  At this point, the vampire series may only have to look out for it's own new chapter, "Eclipse," to, um, eclipse it's current mark. This is clearly a bit of a disappointment for Marvel Studios, distributor Paramount Pictures and Marvel's new owner Walt Disney Studios.

All is not lost, however.  The Jon Favreau flick is still expected to make between $120-135 million for the 3-day.  That would place it fifth all-time behind current record holder "The Dark Knight," "Spider-Man 3," "New Moon" and "Pirates of the Caribbean: Dead Man's Chest." The concern, for the studios, is that pre-release polling predicted that "Iron Man 2" would challenge "The Dark Knight's" record $158 million 3-day mark which it clearly won't.  Because studios count on these polls to determine how to plan their marketing spends, nerves get rattled when the results are this "off."

Additionally, the figure is still a huge jump considering two years ago the first "Iron Man" opened to $35 million.  With amazing word of mouth that picture actually had a 6% jump from Friday to Saturday and ended up with $98 million for the weekend (15th all time).  The sequel flick could easily get a similar family/kid bounce or hold today.  Or, not.

As expected, the rest of the box office dropped significantly under the hype of Tony Stark's return.  Last week's champ, "A Nightmare on Elm Street," fell a whopping 79% from its opening day for another $3.3 million and an eight-day gross of $42.6 million.  Nearing the end of their runs, "Date Night" found $1.6 million for a new cume of $77.1 million and "How To Train Your Dragon" grossed $1.5 million for a total of $195.8 million so far.  Coming in fifth was "The Back-Up Plan" which has made $26.4 million to date.

Look for complete weekend estimates tomorrow on HitFix.

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