The latest version of the Dragon program was demo'd on one of the tele auction sites and supposedly could take 160 wpm with very little training.
Would take that with a large pinch of salt but I've just obtained N S v5 and hope to give it a whirl soon.
The main problem with previous attempts (IBM's ??? Gold??) was that the mic needed an in-line amplifier which was not included and appears to be unavailable