For a while now we've been trying at work to get rid of the last non-packaged dependencies for our applications. We already used NuGet for std things, e.g. nunit.framework, specflow, moq, should etc. and our own internal libraries but we just had some unmanaged dlls that we couldn't get around. Now we can package these up and use another "new in 2.5" feature, import props and targets, to automatically copy our unmanaged dlls over to the bin/debug directory. This means that it all works nicely under F5, and also under Resharpers test runner, but not under NCrunch.
When you are using NCrunch you also need to configure Additional files to include to ..\packages\xxxx.1.0.17038\lib\native. Unfortunately this needs manually updating should you refresh the NuGet package to a later version.
I had a thought though, just as NCrunch already allows you to call the post build step, I wonder if you would consider letting us specify a some additional msbuild targets to run too. That way the imported packages can still be called so our test dependencies are handled, and NCrucnh can still warn us that we are slowing down the build by calling these additional targets :-).
What do you think?