optimized websites for tv channels
I think the most exciting thing about Google TV is the possibility for the various TV networks and content producers to "tweak" their websites for viewing on TV ... and the viewer to seamlessly switch between the broadcast and online/on-demand ways of delivering TV shows. I already have a laptop; if I'm going to surf Facebook I'll just use that. The different thing that Google TV can provide is a way to get video/audio content that is best enjoyed on a bigger screen, and watched with family/friends, to a single device/screen.
Secondly, the future ability to get Android apps on the TV, because if there are any problems the manufacturers or Google won't solve, some enterprising developer will.