I personally never saw the point of Ping myself, but Apple tried to push the social network for music, and failed. Miserably. Instead of continuing to support the sinking ship that is Ping, Apple have decided to ditch Ping and use their strong partnerships found in social networking giants Twitter and Facebook to make Apple's various software and service offerings in the social scene that customers actually care about.
Even though Ping is available in iTunes 10.6.3 and the iOS 6 beta (where it doesn't work), it will disappear in the next major release of iTunes which is due this fall. After that, Apple will use Twitter and Facebook for their social networking needs.
Did you even use Ping? Ping never really even made my radar...
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