I have promised to keep delivering the documentation as it is ready here on the blog, so the most obvious way to start is with an outline. The new topic in our developer manual will cover following subjects. If you think we are lacking something, don't hesitate to leave a comment.
I have got burned last time by publishing the roadmap before everything was done, but... let's just say I didn't learn anything from it. On the more serious note, I prefer to keep you up to date as much as possible and in the loop, even if it means an avalanche of the "hurry up" comments and emails. So, we'll be publishing the topics from the outline below as soon as we can here on the blog. The developer manual updates will happen a bit less frequently, but we'll make sure we update the actual manual as well.
Sitefinity 3.6 - new backend architecture