The team responsible for incorporating speech technology into Windows Vista, among other products, has a new blog called Speech @ Microsoft. Their blog started just this month and inaugural posts cover such topics as using speech APIs (COM or .NET) in applications and which languages are supported by Windows Speech Recognition and TTS (text-to-speech) in Windows Vista. If you're interested in Windows Vista's speech recognition capabilities (you did know that it's present in all editions of Windows Vista, didn't you?), then keep this blog on your radar.
I'm sure they have come a long way since the red faced reception at Redmond demoing the speech wreck-cognition in which the screen displayed anything but what was being said. Microsoft later blamed this on "ambient background noise".