I just came across this post looking at the changes between the .NET framework 3.5 and .NET framework 4.0 Beta 1.

What really interested me was the writers usage of a tool called NDepend. Which allows you to write CQL (Code Query Language) queries against assemblies as if they were a database. Not only is this great as demonstrated in his example for comparing the diference between two versions of an assembly but it is great for figuring out dependancies or for checking coding standards.