We talked about Nokia's App Highlights app (odd to say, no doubt) a little while ago. It's similar to other apps in the Marketplace that bring attention to certain, very popular apps or "must haves". It also showcases apps for local developers in certain regions, giving the spotlight to indie devs who may be lost by the big software houses.
The app itself is not too remarkable but it's not bad either. You can shake the phone to get a "surprise me" feature, similar to IMdB on Windows Phone. It also has push notifications and a Live Tile for app updates, with the former missing from Windows Phone currently. Overall kind of cool and great for people new to the platform, but old hands familiar with the OS will quickly grow bored.