It would be a big surprise if James Cameron's "Avatar" didn't win its seventh straight weekend, but based on Friday's box office the challenge from Mel Gibson's "Edge of Darkness" is slightly more serious than industry pundits believe it would be.

"Avatar" grossed another $7.5 million on Friday for a staggering new domestic total of $572 million.  If recent trends hold, the Oscar frontrunner should end up with around $20-22 million for the weekend and is within days of topping "Titanic's" $600 million record.

Gibson's first starring role since 2002's "Signs," "Edge of Darkness" found $5.7 million for what could be a $16-18 million opening frame. "Darkness" is performing right on target, but could "Avatar finally be slowing down?  Sunday's estimates will tell the tale.

Among other newcomers, "When in Rome" slightly overperformed Friday with $4.3 million.  The Josh Duhamel/Kristen Bell romantic comedy was only projected to do a weak $9 million for the weekend, but a slightly better $12-14 million looks more likely.  That's not the result Disney was hoping for, but new studio head Rich Ross isn't making things easy without a new head of Marketing place yet.  They all can't be easy smash hits like Johnny Depp's "Alice in Wonderland" is expected to be.


Look for complete weekend estimates tomorrow on HitFix.