Wireframe drawing application used by Microsoft for the MVC roadmap

Can anyone tell me which application is used to draw the following image:

enter image description here

This image was taken from http://aspnet.codeplex.com/wikipage?title=ASP.NET%20MVC%204%20RoadMap

Solution

That looks like a screenshot from Balsamiq Mockups to me.

I use it a lot myself, and it's a very good application to quickly draw up a mockup version of a program you are going to create, either for your own use, or to show to a client/customer before starting the actual development.