I took a look at some of the recommended settings for a few games it detected (BF3 and FC3...it didn't detect any of my Steam games for some reason). Generally speaking, it might be a good starting point for someone who does not like to tinker or who doesn't read graphics card reviews, i.e., no one on this forum. For both games it detected, it chose settings way below what I play at, especially Far Cry 3. That's not necessarily a bad thing, since you'll get a good playing experience, but in general, Nvidia's bias here is going to be to drop graphical settings to avoid making its cards look less than capable.
EDIT: I refreshed the app list and it picked up three more games - Deus Ex: HR, Fallout: NV, and Max Payne 3.
Overall, I'm starting to think this is actually a pretty cool application. Particularly for games with a great many detail options, GeForce Experience adds a lot of value. It provides screenshots of games and highlights areas of the screenshot that are benefitting from a particular detail option. It would be even better if it showed before and after screenshots, but that would be a lot of work for some games.
By the way, who knew I had my "specularity fade" in Fallout: NV at a non-optimal setting of 20 instead of 15???
On the other hand, it's recommending I turn off tesselation in MP3 and turn on 2x MSAA. I'd call that a non-optimal optimization for overall graphics quality.