He was the first writer/director to get a film past the $1 Billion world gross mark with a single film and this week James Cameron becomes the first writer/director to pass the $2 Billion dollar mark in world box office takings, with a single film.

James Cameron must be having a good year, his return to film making after a 12 year break has beaten his own box office landmark film Titanic, all in the same week that 12 years after he won his first Oscar, he's nominated for another, although he has tougher competition this time (his ex-wife!).

In 1998 he set the box office alight and Titanic took $1.8 Billion in box office grosses, passing a milestone figure that took another 5 years before a film would pass it again, and this week another milestone is set as Avatars gross reaches $2 Billion, but unlike Titanic in 1998 Avatar still has some mileage left in it.

With the rate of tickets being sold the possibility of Avatar reaching $2.5 Billion is not out of the question, $3 Billion could be a stretch thought.

To look at this correctly though we need to take into consideration inflation, cinema tickets cost nearly half the price in 1998 as they do in 2010, which means that per head watching Titanic on the big screen it's probably still ahead of Avatar, but the gap is certainly closing fast.

Titanic of course isn't by a long shot the biggest film by the number of tickets sold, that honor goes to Gone With the Wind, which may never be beaten. Another thing to remember, boosting Avatar's box office takings is the appalling extra charge for the glasses if you choose to see the film in 3D. So until Cameron's next film Avatar will probably sit pretty as the only film to gross anywhere near $3 Billion pound?