The h.264 codec may have only recently, i.e. in the last couple of years, surfaced in the public discussion and may have only recently taken over the web, but it's been around for a decade. It may be the "cutting edge" but it is getting a bit long in the tooth. Fret not, fans of closed video codecs owned by large corporations, its successor, HEVC or h.265 is coming.
Granted, technologically, HEVC, or High Efficiency Video Coding, sounds pretty good. It boasts the same quality as h.264 while only using up half the bandwidth, great for online video, especially on mobile devices. It's also more efficient to decode, especially on multi-core processors, and bumps the resolution limits to 7680 x 4320 px.
The obvious question is whether this will spark yet another format war. H.264 obviously won the first one, though Google is not giving up on V8 and WebM. But h.265 may face a tougher fight. Then again, if it is significantly more advanced than its competitors, it's not going to be much of a fight.