My boyfriend and I are writing a series of books and we are using the site "wikispaces" to share documents and chapters. It is a private site, only he and I have access to it; no one else can see it. Would this still be considered self-publication? Would there be any implications from going about it this way?
If only you two have access, it remains a private communication. That would not be considered publication. Just make sure it remains secure. Use strong passwords for access, and change them on a regular basis. I strongly suggest you have a collaboration contract in writing before you begin. Many a friendship has been destroyed by collaboration on a writing project without a clearly stated statement of rights, roles, and expectations.
absolutely!!! here's the best one: http://wga.org/uploadedFiles/writers_resources/contracts/collaboration.pdf with the change of a few words it works as well for books, as for screenplays...