Sorry to say, but the report that led many people to believe two new Matrix movies were on the way, and both would be in 3D, were completely fabricated for no other reason than to spread a lie.
Administrators at the London school have come forth to say Keanu Reeves didn't even have a scheduled appearance there at all this week. Whoever it was who started this story was just making stuff up out of thin air.
After the school denied the story, Reeves's people did as well, saying the reports were completely bogus and there is no official word on any continuation to the Matrix movie franchise.
The initial rumor said that not only was The Matrix 4 on the way, and set to be filmed in 3D, but there were already plans for The Matrix 5 to come out as well.
The report also suggested that movie producers had been in talks with James Cameron to get tips about how to create the best 3D movie experience. Cameron hasn't responded to that apparently bogus claim but it's pretty clear now that that hasn't happened.
So, unfortunately, your dreams of seeing a Matrix movie filmed in 3D may not be as close to reality as it seemed just a couple days ago. And apparently anyone can just whisper complete inaccuracies and get them picked up all over the news media. That's how the Internet works.