Microsoft may have incorporated speech recognition tools in Vista, but for people who have been using Dragon software, for ever so long, this addition by Microsoft comes in the "thanks for nothing" category. They will continue using Dragon because they are so used to activate everything through voice that the do not want to use the keyboard facilities which are so integral a part of the Microsoft speech recognition program.
Besides this, Microsoft speech recognition playback systems have that constipated voice of Microsoft Sam Reading back your message to you. Why would you want to hear that computer-generated tones, when you can hear dragons' professional voices reading back your messages to you in a more human manner.
Microsoft is trying desperately hard to sell Vista. But all these gadgets do not make it a desirable product when you have tried and true thoroughly professional voice recognition software like Dragon and Viavoice in the market. It is almost on par to a kid Fresh out of kindergarten, yelling for attention in a conference full of University graduates.