Google Chrome 11 additional support for HTML speech input API. "With this API, developers can give web apps the aptitude to transcribe your voice to text. When a web page uses this feature, you simply click on an icon and then speak into your computer's microphone. The recorded audio is sent to language servers for record, after which the text is typed out for you."
Google Translate is the first Google repair that uses this feature. If you use Google Chrome 11 Beta, Google Chrome 12 Dev/Canary or a recent Chromium build and visit Google Translate, you can click the voice contribution icon. Right now, this characteristic only works for English, so you need to select "English" from the list of input languages.
Unfortunately, the results aren't great. I tried to interpret "beautiful sunshine" into French, but the speech-to-text engine didn't work correctly and Google had to translate "wake up beautiful sunshine girl".