Can I stream from Safari silverlight to AppleTV? I'm using Sky Sports Now TV to watch live sport on my Mac. This is via the silverlight plugin in Safari. Can I use something to divert this video feed to my Apple TV so I can watch on my television without using a cable?

I should clarify, I need a solution right now since I want to watch the Heineken Cup rugby final starting now and I have a 2009 MacBook Pro so I can't use AirPlay.
AirPlay can mirror the display of your mac to the AppleTV. This only works with 2011 model macs and newer running Mac OS X 10.8

more details:
http://support.apple.com/kb/HT5404