For six straight weeks "Avatar" has overcome every challenger that has tried to knock it off the top of the box office and this weekend was no different.

"Avatar" grossed yet another strong $30 million over the weekend for a new domestic total of $594.4 million.  That stunningly puts James Cameron's blockbuster only days away from passing "Titanic's" U.S. mark of $600 million, a feat inconceivable less than two months ago.  With numerous Oscar nominations expected on Tuesday morning, it's unclear how high "Avatar" can go.

Showing a solid start in the second slot was Mel Gibson's first on screen role since 2002's "Signs," "Edge of Darkness."  The Martin Campbell thriller made $17.1 million which was slightly higher than Warner Bros.' expectations.  With strong audience response there is no reason to believe "Darkness" couldn't finish between $45-55 million domestic.

Among other newcomers, "When in Rome" slightly overperformed $12.1 million and the third slot.  The Josh Duhamel/Kristen Bell romantic comedy was only projected to do a weak $9 million for the weekend, but scrounged some extra dollars from uninformed moviegoers.  That's still not the result Disney was hoping for, but new studio head Rich Ross isn't making things easy without a new head of Marketing in place yet.  They all can't be easy smash hits like Johnny Depp's "Alice in Wonderland" is expected to be.

In fourth place, Dwayne Johnson's "Tooth Fairy" was down only 37% proving its pulling out good word of mouth with the family audience.  Another $10 million brings its current cume to $25 million.

"Book of Eli," which found fifth, is a significant hit for leading man and co-producer Denzel Washington. The post-apocolytpic thriller grossed $8.7 million over the three day for a new total of $74.3 million.  It's the second success in a row for financier Alcon Entertainment and Warner Bros. after "The Blind Side" and should end up with around $85-90 million when all is said and done.

Next week, "Avatar" faces its biggest challenge yet as the Nicolas Sparks melodrama "Dear John" with Channing Tatum and Amanda Seyfried arrives to make teenage girls cry from coast to coast. Can "Avatar" go for eight straight?  We'll see.

Complete weekend results are released on Monday.