i don't know anything about this really but when i was looking at tvs they told me in order to connect and watch hd stuff via your comp, that you needed a special video card otherwise it was like watching standard def tv on a 1080 hd tv
you wouldn't see a difference
again i don't know anything about it, maybe macs have the video card you need already or maybe the new modles are going to come with it
who knows, not me