One of Microsoft's employees posted a podcast to discuss the new Voice Recognition features of Windows Vista:
The long night of waiting is over. Windows Vista is deep into the Beta and CTP programs. Some of the features are recognizable from Windows XP, while others are so absolutely amazing they will knock your socks off. One of the new features is the built in Voice Recognition. I took the time to make a short demonstration on how to set it up and use it. It is so impressive! Don’t take my word for it. Watch the podcast and see it for yourself, then try it on your own machine.