I've seen them in use at schools recently for speech therapy I think. The school got a grant for 5 or 6 macbooks plus software that came with headphones with mics etc.
It's been my experience with voice recognition that it's more of a novelty and interesting idea than a productive thing. BUT there are rare cases I see from time to time where it's being put to extremely good use. Professionals are using cassette and other handheld recorders and then pass them off to their secretaries/assistants to transcribe into text files. Those assistants use this software to transcribe in and then clean it up by hand. That's usually how you have to go with it, it's never perfect and can leave some very silly and obvious mistakes in the text files if you don't look them over carefully when it's done.
I played with the speech control on the mac a few times, but again it was more of a "that's neat" but too awkward to use. I bet if I was a paraplegic it'd be awesome though. Not useful for the normal non-disabled person though.
As for dragon specifically, they've been on mac for years haven't they? You sound like you looked for it but didn't find it.
