Graham was recently looking for decent speech recognition software recently. I gave him the only thing that I had, an old version of Dragon Naturally Speaking (v.4 or v.5 I believe).
ScanSoft has released version 8 of Dragon Naturally speaking. They claim they have made it 25% more accurate and in the article quoted above, David Pogue claims he is able to write a column with 100% accuracy. This could be an option for a future review.