If you have Netflix and a Mac, surely you’ve been frustrated that you’ve been locked out of Watch Instantly since it was launched long ago. Today Netflix started allowing Mac users to opt-in to the Mac streaming beta. To get your account added, head over to http://www.netflix.com/silverlightoptin and install the Microsoft Silverlight plugin. Apparently there is a 5 device limit to the beta, so keep that in mind as you activate computers. Hopefully it will go away after the beta is over.