We've talked about this at length internally. I am (as I believe are taylor and goob) open to suggestions, and would welcome experienced hands.
We actually also talked about a SVN conversion, since we are a little concerned about the long term stability of the current CVS host. Someone just has to have the time to do it. I agree with taylor, though, we don't use CVS right as it is, if we tagged builds and branched appropriately, you could just download revision 573, etc with the current system, and that has been a long running problem, The folks who have tried have not been particularly successful, and there is a far amount of it for just one guy to make it all work right if that guy has anything else going on in his life

The SCP greatly discourages branching (We try to keep it to two branches at all times, HEAD and stable[currently 3.6.9 branch]), and I've NEVER heard of anyone doing a partial branch on any project.
Context is important here, we discourage it because it tends to get out of control, branching needs a little care and feeding in CVS, and some dedicated developer time to making sure its kept up to date. We've tried it a couple times, and ended up with messes each time. So its sorta a ban thats fed on itself, not for any good reason other than a couple of largish mistakes.
All of which puts us where we are, organizationally. We can attack it one guy at a time, or we can make sweeping, wholesale changes. The former frustrates the people who are waiting for us to do it right because it takes too long, and the latter frustrates the people who have been around a while who think that change is too painful. In an all volunteer org, incentives for change are hard to come by.
Currently there's no way for anyone that isn't a dev to follow fs2open progress. And if I can't see if the project is alive, why should I bother to join it?
But you know it is alive, just a little disorganized. Sounds like you might be able to help that

How would one join the SCP, BTW?
If you are new to things, bug hunting is a great way to help out. If you are a new coder, and think you know how to fix something, fix it and submit a patch. If you are an experienced coder, send me or goober a PM.