Las Vegas and Hong Kong both have baggage systems in which paper bag tags have RFID chips imbedded in them, but the technology hasn't spread.

WSJ: Flying Through the Airport

One example: NPS influenced JetBlue's choice to offer customers one free checked bag when rival carriers began instituting baggage fees.

WSJ: What United, American, Delta, Southwest, JetBlue, Alaska, Virgin America Airlines Learn From Customer Surveys

An additional app alerts passengers as their baggage approaches on the carousel, making it easier than ever for them to find their bag.

ENGADGET: Trakdot Luggage hands-on: find your lost bags Hands-on