Google isn???t the first one to work on an alternative to AirPlay. In fact, the widest-supported AirPlay alternative actually predates Apple???s protocol: The Digital Living Network Alliance launched in 2003 to bring content sharing to the living room. It???s DLNA protocol has been widely adopted by numerous players, with a total of 500 devices supporting DLNA today. However, the actual level of support varies widely, and many manufacturers have opted to roll out their own branded solutions on top of DLNA ??? but even those see little use from consumers.
via gigaom.com