Valentine’s Day soared to the top of the box office this weekend, taking in $52.4 million over the past three days. Percy Jackson & The Olympians: The Lightning Thief came in second with $31.1 million and The Wolfman was third with $30.6 million. Avatar fell to fourth, its lowest position yet, with $22 million and Dear John rounded out the top five with $15.3 million. How to explain the success of Valentine’s Day? Old friend Paul Dergarabedian knows: “To have a movie titled Valentine’s Day on Valentine’s weekend was a no-brainer that absolutely worked.†Exactly! [AP]