Although officially unconfirmed, there are reports (a press release by the Hollywood Reporter) that the two parts of Harry Potter and the Deathly Hallows will hit the cinema in 3D. Part one arrives in November 2010, and part two in July 2011. Rumours are that Warner has commissioned the conversion of the films into 3D as a result of the success of Avatar, which has become the highest grossing film of all time.
How the “conversion” compares to actual deliberate filming in 3D is not clear. Apparently the costs are $5 million per film conversion and another $5 million to hand out the 3D glasses in the cinemas. If the 3D conversion works well, it would be an easy commercial decision to make.