It's not new by any means ... but I'm absolutely astonished how well it works!
I tried youtube out with the HTML5 player enabled (link (http://youtube.com/html5)) and I can't even tell the difference! I can see Flash and Silverlight becoming irrelevant in the near to distant future (Though, at least moonlight runs on FreeBSD).
Pretty neat to be using youtube on a FreeBSD machine without setting up Linux emulation to run flash!