One recent example of the collaborative model is the Business model and design blog and it's book chunk project. The readers are supposed to pay USD 24 to receive the upcoming book in small parts, perhaps every chapter. They are also asked to contribute and do some sort of "beta testing" of the book.
There are mostly positive comments on thins on the blog even though some of the readers suggest that the subscribers also would receive a copy of the finished book.
So far so good. As long as it is used in a thought through way I do only see good outcomes from such collaborations. But there might be rights issues to the end result which has to be solved in some good way.
There are already existing models for collaborative creation of software. But they are created more as licenses and perhaps not good in a situation as the one described above where two "main writers" only use the ideas of others as it fits them. Not as a main part of the whole creation process.
As I understand the Business Model book project it will only use the readers for input and not as much for contribution, but still there might be a need to think through how to construct the models for larger collaborations, online or offline.
Perhaps is it enough with some sort of acknowledgment to fulfill the rights of the contributors, but there might be cases where there is need for new models for cowriterships and how to share revenues and rights. I see the rise of crowds as creators as something which we will see more of.
One good example of how this is used is the Wikipedia book project in Germany. It is allowed under the Wikipedia agreement to reproduce but it has to be under the same terms as the basic texts. The revenues will however, as I have understood it, stay at the German publisher.
This will rise the need for a good model for revenue sharing in collaborative environments where the content is jointly created but the economic extraction is proprietary.
Have anyone good examples how this is done today, or has there not been any need for this yet?