With Avatar the reigning champ and Sherlock Holmes still to come, Hollywood crossed the $10 billion line for the first time in U.S. and Canadian ticket sales for 2009.  Through Sunday, the total stood just $36 million short of crossing the $10 billion line, according to tracking firm Hollywood Box Office, and was set to plow across it Tuesday night.

The year’s top box office attractions were Transformers: Revenge of the Fallen and Harry Potter and the Half Blood Prince, and with hits like Harry Potter and The Hangover, Warner Bros. was the North American box office champ among studios.  And with both Robert Downey Jr.’s take on Sherlock Holmes and the return of those rascally rodents in Alvin and the Chipmunks: The Squeakquel coming in time for Christmas, the final take is expected to top $10.4 billion.

Hit the jump for a list of the top 20 domestic box office hits of 2009.

With only hours to go before Hollywood’s golden season draws to a close, I thought it was a good time to do the post-mortem on the summer of 2009.  By now you may have heard that this summer was Hollywood’s most-profitable ever with grosses topping $4.3 billion. But has it felt like the biggest summer ever?  Not really.  Blockbusters like “Transformers 2″ and “Harry Potter and the Half-Blood Prince” aside, 2009 was a season of expensive movies that didn’t live up to the hype and cheap movies that performed above all expectations.  Follow me now into the murky world of box office number crunching to see just how huge Hollywood’s hugest summer really was.

The fact that Pixar would take number one this weekend with its tenth feature release, “Up”, was never in question.  The Disney-based studio has built a reputation for quality and success that has stood unchallenged for over a decade.  The only real question for “Up”, the first of Pixar’s toons to be released in 3D, was how high it would soar.  The film’s cranky old man protagonist was a potential stumbling block as was the continued presence of the similarly family-geared “Night at the Museum” sequel.  So how did “Up” fare?  With $68 million over its first three days, the animated adventure bested Pixar’s $63 million take for “Wall-E” in 2008 and came within spitting distance of the $70 million starts from the studio’s top two earners – 2004′s “The Incredibles” and 2003′s “Finding Nemo”.