I was recently reading a fairly detailed comparison by Andrey Shchekin of the various injection containers out there in the .NET space. I found it interesting that the last feature he regarded as important was the ability to tell the container to mock a particular object. Now, when I wrote an article about evaluating IoC containers, it didn't even occur to me to include this. Now, Andrey includes many points that I haven't covered, like the fact that Castle hasn't had a stable release in well over a year, but on this point I think it's best left out....