Thanks for writing to us. O'Reilly's Production toolchain supports both DocBook 4.4 and DocBook 4.5. We don't currently have any plans to support DocBook 5 in the near future.
Are you a current or prospective author for O'Reilly? If so, we'd be happy to discuss authoring options with you in more detail.
Publishing Technology Engineer
O'Reilly Media Inc.
Neat. Never figured I'd get a response, within the first few hours no less.
And, no. I'm not a current or prospective author, I couldn't write a book even if my life depended on it. I'm just very curious. I've been reading up on DocBook for the past week, for a personal project and happened to stumble upon your authoring docs. Very helpful documentation, I must say. However the 4.x rather than 5 caught my eye, and I just had to know.
That said, I'm really rather enjoying working with DocBook. Should the unlikely event happen, that I find it within myself to write a book (provided it's a suitable subject), I'll definitely contact O'Reilly about it.
Forever grateful for you taking the time to reply.