Slowly catching up on this mailing list, so I apologize in advance for the late reply.
The point here isn't to debate "which markup language should we use", it's to solicit volunteers to actually write the *content*. I've volunteered many times before (and will continue to do so) to convert whatever you write in just about any format (text, asciidoc, rst, markdown, pencil and paper) and convert it into DocBook or anything else the Docs team thinks is appropriate. I'll even proofread, edit, and help organize. What we need is content!
If there's a particular cloud-related topic you'd like to write about -- go write! And then we can worry about the tooling, once there's some content to work with.