All publicity, it appears, was good publicity for “Mr. and Mrs. Smith,” which 20th Century Fox opened this weekend to $51.1 million — the biggest opening in the careers of both its stars, Brad Pitt and Angelina Jolie. But “Cinderella Man” shows there is a flip side to that coin. With star Russell Crowe at the center of his own media maelstrom following an assault arrest in New York, the pugilist pic slumped 48% in its second week to $9.5 million, a much steeper decline than Universal had planned when they slated it for a summer premiere. After months of Pitt and Jolie as the tabloid media’s most sought after (alleged) couple — Us Weekly is reported to have paid as much as $500,000 for photos of the pair on an African beach together — Fox launched the Doug Liman-directed film in 3,424 theaters to biz significantly higher than expected. Elsewhere, however, the marketplace remained sluggish, with the frame’s other new titles debuting softly. Dimension’s Robert Rodriguez kidpic “The Adventures of Sharkboy and Lavagirl in 3-D” opened at No. 5 with $12.5 million from 2,655 locations. In seventh place, Paramount’s “The Honeymooners” saw results somewhat lower than expected, with $5.8 million from 1,912. And finishing in the 11th spot, Lions Gate’s French horror film “High Tension” opened to $1.75 million at 1,323. There’s plenty of disappointment over the lackluster second-week results for U’s “Cinderella Man,” which now has grossed $34.5 million and, barring some unforeseen uptick, will have trouble matching the $77 million domestic gross of last summer’s “The Terminal.” In second place for the frame was DreamWorks’ “Madagascar,” which in its third week grossed $17.1 million, raising the total on the talking animal toon to $128.4 million. Immediately behind it, Fox’s “Star Wars: Episode III — Revenge of the Sith” continued its stellar run, pulling in $14.9 million in its fourth weekend to lift the domestic total on George Lucas’ sci-fi finale to $332.1 million. Adam Sandler football movie “The Longest Yard” from Paramount was at No. 4 with $13.5 million in its third week. The total on the remake is a more-than-respectable $118.1 million.