I've only just started using Dictate, and so far I'm delighted. My only gripe is that the type in the Recognition Window is just too small. Perhaps I've overlooked how to do this, but I would really like to be able to increase the size of everything about this window.
Also, I think that you should have the option of clicking a button to edit the items in the list that this window produces. Saying "edit 5" etc works most of the time, but 'most' throws up its own difficulties.
Overall, though, a great program.