Of all the films to unseat Avatar's domination over the box office, I doubt Dear, John—which I hadn't even heard of until watching cheeseball Sandy Kenyon trash it on Taxi TV last night—was the frontrunner to do so.
However, the Mighty Blue Dicktails of the Na'vi Tribe were no match for another Nicholas Sparks book about people writing things to each other while being pretty and sad. Per the LA Times:
In the first major box office shocker of 2010, tearjerker "Dear John" displaced "Avatar" from the top of the chart with a very strong $32.4 million opening in the U.S. and Canada, according to an estimate from distributor Sony Pictures.
James Cameron's 3-D spectacle "Avatar" took in $23.6 million, bringing its domestic total to $630.1 million. "Avatar" ticket sales were down 25% on its eighth weekend. That's the science-fiction blockbuster's second-highest decline since it launched, demonstrating that it was affected by the new competition.
Affected? Somewhere, James Cameron is in the fetal position, as if he giant Tree of Blue Sparkly Life was just cut down by The Man. And not just The Man, but The Man Who Knows How to Talk to Women. Human women. The irony of a guy whose failed relationships are attributed to his workaholic habits being unseated by a weepy, saccharine sweet romance movie about people writing things to each other using actual pen and paper—so analog— is kind of glorious. Also, the nicest thing said about Dear John, via Metacritic, came from A.O. Scott at the New York Times, who noted:
Dear John carefully distills selected elements of human experience and reduces them to a sweet and digestible syrup. It may not be strong medicine, but it delivers an effective, pleasing dose of pure sentiment and vicarious heartache.
If by "effective" you mean "Dicktail Circumcising," then by all means, yes. Also, this goes without saying, but whatever was going to unseat Avatar was going to be a "shocker" regardless, as movie theaters might finally be getting used to the acne-prone masses of now perpetually four-eyed depth-perception challenged individuals spending their weekends fantasizing about six feet short of D & D meeting in the middle with Smurf Sex. As Cameron has no doubt learned by now, there's no substitute for the Real McCoy, be it in human-to-human love, or penises that double as ignition keys for flying wombats of death. Long live The Dicktail.