It may not be the first but it is a reason to upgrade from HTTP/1.1. PING frames have other uses too, like being able to estimate connection latency in an application, rather than trying to read it from the kernel. This can be used to load balance across connections, or estimate the bandwidth delay product of a connection. PINGs have a lot of uses; the new thing is being able to control it from an app rather than it being OS specific.
