Michael Lehman posted a great Blueprints 101 video on Channel 9. http://channel9.msdn.com/posts/MichaelLehman/Microsoft-Blueprints-101-The-SimpleEdit-Blueprint/
In this video he shows how to consume a Blueprint which guides a developer to customize an application (and its parts) which is unfolded into a Visual Studio solution. He also shows the deep integration with Visual Studio which is core to the Blueprints system which I’ll overview below.
The Blueprints Manager off of the Visual Studio Tools menu shows what Blueprints are registered/installed on your machine. This is the list of Blueprints that you can unfold. It also shows the Blueprints that have been unfolded into the currently open Visual Studio Solution.
You’ll also notice that he right clicks on projects in the solution and there is a context menu item which is not usually present, namely the ‘Blueprints’ menu item. In this Blueprint (the one he unfolded at the beginning of the video) he decided to add two menu items to the main Visual Studio project (BPEdit), namely ‘Add Load/Save Filter…’ and ‘Add Options Dialog…’ As a Blueprints author (when you design your own Blueprint) you can define any actions which you want to expose to the Blueprint consumer. In this case, for the ‘Add Load/Save Filter’ he’s adding a new C# file which is the Load/Save filter. The guidance (which is part of the Blueprint) explains how to connect this filter.
Speaking of the guidance, every Blueprint contains, at least, some guidance related to its topic. I say at least because the smallest Blueprint you can create is only guidance. The Blueprints guidance can be seen in the Visual Studio ‘Workflow’ Tools (dockable) window. You’ll see that it can even keep state about what has been accomplished (ie. checked) in an unfolded Blueprint.
In this case, Michael is showing how to build an application that is made from specific type of application (an editor application). This type of pattern reuse is very powerful for companies/developers which are building applications with a core set of libraries/concepts. For example, a consulting company which creates social networking web sites might create a Blueprint to unfold the User Management features of the social networking site. That might include pages, database code, or other parts of the site. Then the developer can extend the pages to provide a unique look and feel for the specific customer’s brand which needs the social network.