Since the point of these projects is partly to generate content for the main site, most of the techniques you learned should result in new questions or references to existing questions. I think it's also important to list the tools you used, in case someone wants to rise to the challenge and build the project using tools that nobody else has used yet--possibly spawning even more new questions.
It would be nice if we standardized on a concise format such as that shown below, keeping the prose to a minimum. I think only the tools used and the questions spawned or referenced should be required. If someone strays from the suggestions given in the question, it would be helpful to summarize those changes in a brief intro.
It isn't clear to me if the community projects are also intended to showcase people's work, but if so, it makes sense to encourage including other optional sections.
Brief intro (optional)
If you built the project but strayed from the suggested materials, tools, and techniques, this is the place to summarize what you did differently.
Instead of using pocket screws as suggested, I used hand-cut dovetails.
A photo of the finished project. In-progress photos are not necessary, as they will probably already be covered under the linked questions.
If you strayed from the suggested materials (or if there was no suggestion), you may include that here.
Quarter-sawn red cedar
A list of the tools you used (or tried to use) in the process of building a project.
Brief of your finish, if any. For example, you may say that you painted it or that you applied 5 layers of wipe-on poly over stain. If you left the wood bare and don't plan to apply finish, you may simply say none.
My new questions
New questions you posted while working on this project, if any.
Other helpful questions
Other questions or answers which you would recommend reading when building this project. You should definitely include existing questions you personally referenced. You may also optionally include questions you think would be critical for a new woodworker who is building the project.