Developers can now add up to 255 characters of keywords to their applications when they submit to the App Store via iTunes connect. These keywords will provide the App Store with (hopefully) better search results that could make finding the right app for you out of the 65,000+ applications available easier.
The update from apple says
It is important to enter keywords for all applications as soon as possible so your application can continue to be successfully located on the App Store . . . Keywords can be updated with the submission of a new binary.