I have also avoided writing about a project I'm part of, mainly because I've been wrapping my head around it. I am working on a collaborative novel with a few other Melbourne writers. We are each writing chapters and developing characters, which will be interconnected and move together with a larger plot arc we all share. The process of it has been so different from how I've usually worked, that is has taken some getting used to. But it made me curious about the ins and outs and potential failures collaborative writing can bring. The plus sides are that there are so many more minds to draw from for creative ideas and directions, and as such the content can power along so much quicker with all those people working on it. The downsides are that all of the problems you face as a solo novelist are multiplied by the amount of people working on it. Writing something new, it can often be hard to both write blindly and also steer it into a certain direction. There is a lot of tentative feeling around and playing with what works, and those bits and pieces eventually become interconnected plot strands and a character revealing itself to an audience chapter by chapter. Adding another person to it, you have to be in sync with what they are doing. But if all of you are in that tentative, new stage of growing the story it can come out garbled or not quite connect. It can potentially be more work, especially if you are novices.
If sound like I am criticising it a lot, it's just because I am trying to process how it works and doesn't work as a way of creating new writing. I'd like to work collaboratively in the future, because a lot of professional writing can happen in groups - for example television scriptwriting.
In my travels - well, when I googled 'collaborative novels' - I found a lot of sites dedicated to it. Many, like Novelet and Storymash look like hideous monstrosities from the late 90's. Protagonize is pretty active, but when I had a poke around it felt like a less crazy version of fanfiction.net (shudder). So I guess the best way is to learn by doing. And now I've gone full circle. The end.