Any webcam is supported, including built-in webcams. You may, however, wish to use an external webcam or video source to have better control over where your camera is positioned and controlled.
Depending on how much space you are hoping to occupy with your studio, you may want to use an external webcam or video camera mounted to a tripod to have better control over the framing of each studio participant.
External webcams are also often bundled with software that allow you to control the colour temperature, auto focus and exposure settings of your webcam, which can be very useful. If you are using a Mac, you can check out Sight Control ($6.99) or iGlasses ($19.99) to control settings on your built-in iSight camera.
To use the HD feature on your PRO account, all participants must be using a 720p webcam or better to achieve an HD studio session. Links to HD webcams are listed below.