Hi Mark,
Thanks for posting!
At the moment, NCrunch executes tests in batches and processes the results from these tests in batches. The batching has several advantages (most notably that it operates faster), which is why NCrunch went down this road. However, as you've mentioned, there's a bit of a drawback in that you need to wait for the test to finish executing before you see any results from it.
There are long term plans to adjust the engine so that it will provide console/trace output in real-time using the Tests Window (i.e. while you have the test selected). While this is relatively simple to implement, it can only happen when the core engine itself is fast enough to be able to process these results in real-time without degrading performance. We're not quite there yet ... but we're getting closer!
Cheers,
Remco