It's too early to say if this movie is going to overtake Titantic, as that might be a far stretch, but I think 2nd place is definitely in play at this point.
LOTR: ROTK - $1.119 Bln
POTC:DMC - $1.067bln
TDK - $1.001bln
With the massive international take, and split as mentioned by Reasonable, and the riddiculous drop this past week, the movie is going to have some amazing legs to rival Titanic. Looking at the month of Jan 10, there is nothing on the horizon, except maybe Book of Eli to take the #1 spot. So it looks like Avatar 2 in 2012...