How was Google supposed to do that? Flash (still) doesn’t support WebM, so there wouldn’t be any fallback. Google surely isn’t arrogant enough to make YouTube videos not accessible to more than half of the browsers out there.
There was and still is no realistic way for Google to switch to WebM. Not exclusively. (Yes, they can also encode their videos in WebM but h.264 versions are always necessary.)
There was and still is no realistic way for Google to switch to WebM.
YouTube, no. Chrome, obviously YES. Firefox and Opera did and still do it. Their failure to use Chrome to push WebM means they killed off their own format. Tells you something about their priorities.
There was and still is no realistic way for Google to switch to WebM. Not exclusively. (Yes, they can also encode their videos in WebM but h.264 versions are always necessary.)