Recently in my team we have introduced the use of SpecFlow to held create business driven tests. Specifically we've been refining the way we work with acceptance criteria for some time, and have been pushing towards the Given, When, Then format.
Last week I wrote about my desire for an nunit runner that could execute tests in parallel batches. Specifically selenium tests that were using the nunit framework. It turned out to be pretty easy to implement.
In my new team there is considerable use of Nunit for unit tests, which has been further adopted as a convenient mechanism for all tests. Including a set of selenium based UI tests.