HTML5 Rocks: Capturing Video and Audio in HTML5
Eric Bidelman has posted an in-depth entry on using the upcoming native HTML5-family APIs for capturing Audio and Video using GetUserMedia. While the Spec and APIs are still in flux there is native support in the Android 3.0 browser and Chrome for Android.
The article goes through a little bit of the history of the specs and then dives right into a number of in-page examples.