I agree on the moviemaker issue, but I think the solution is not to merge a lot of different projects but to get developers to join existing projects instead of starting new ones.
One problem is that the infrastructure of free software developing benefits forks and new projects. The GPL makes it explicitly clear that such actions are allowed and encouraged. What it lacks is rules about openness in other ways than distributing the source code. It doesn't force project leaders to accept contributions to the code from newcoming developers. This is, of course, a good thing. Such a clause would be untenable, but it illustrates an imbalance in the system. You have the right to fork a project, but you don't have the right to contribute to an existing one.
So what's to do about it? I propose every project sets up a clear policy on how to contribute, how to become a member of the team, and how to help in other ways. Ubuntu does this excellently: http://www.ubuntu.com/community/participate. As a counter-example, the Linux kernel has a reputation for being difficult to get involved in.
I believe that ease of contributing is the key to becoming a really successful project. You want to get the best programmers on board, so let them know it! Maybe that way we can have fewer and better projects instead of many small ones that don't go anywhere.