Looking at the current offering of GoogleTv apps I think we need to have a discussion about how GoogleTv is different from mobile and what the experience should be like.
The TV is a media browser so put your pictures, movies, statuses, etc. front, center, and full screen. Don’t waste space with large and useless UI elements (I’m looking at you Twitter). The Tv is also multi-user, don’t focus on single user experience; always ask how will your app interact with one to five people in the room.
Apps need to be thought about in terms of “watching” them instead of the normal high level of interaction. This being said, I think apps generally fall in to an active or passive mode.
Passive apps should have emphasis on Visualization (e.g. http://visibletweets.com/). Think awesome dashboards of Foursquare + Twitter + GoogleReader headlines. Think iTunes music visualizers (Pandora you are really boring on my Tv). Think art and how to bring the museums of the world to your living room!
Active apps need to remember that you are sitting on a couch, take hints from how the Wii channels make their interfaces. Furthermore active apps need to get me to their media ASAP (Netflix does an okay job here). Unlike tablets or phones, Tv apps will frequently service the whole room. How do you make an app social for the room? I’d like to see social DJ apps like http://turntable.fm/ on my Tv for my party.
Another way for active apps to exist is in an “overlay” experience. How can I order that pizza without interrupting the re-run of Seinfeld I’m watching?
Currently my favorite passive app is the Classy Fireplace. It starts up full screen with its media front and center. And it is just so damn classy.