New information on the Matrix sequels claims that both Matrix2 and 3 will be shot at the same time, with the editing determining which will be which.
Other new info on the sequels says that the Martial arts director of the original movie will have a starring role alongside Keanu Reaves in both sequels. The Matrix 2 is planned to act as a prequel to the first movie giving some background info on the war that led to the creation of the matrix.
Other scenarios for the much-anticipated Matrix sequels, but nothing has been confirmed. Plots mentioned include a visit to the underground metropolis of Zion, the revelation that Trinity is an agent, the introduction of a character more powerful than Neo, and the discovery of a Matrix within a Matrix.
It is anticipated that the cast will remain largely the same.
The sequel has a planned release for sometime in 2001 (probably summer).