The discussion on Google's decision to remove H.264 from Chrome is still raging, and an argument that is brought up a lot is market adoption.
Now, the primary video to serve video on the web today is Flash. It doesn't really matter which codec it's using because it's played through Flash anyway. But what about native HTML5 video support? Which format will have the widest support in the market? …
Since browser statistics are highly unreliable, this is mostly a theoretical exercise. However, a lot of people like to refer to these numbers, so let's play the game and look at them in more detail. The source with the most detailed statistics is StatCounter.
So, the numbers…
At first glance, the situation is looking very good for the H.264 camp. Internet Explorer is still the #1 browser worldwide, and Safari and IE together have well over 50% market share, according to StatCounter.
On the other hand, Opera, Chrome and Firefox have a combined market share of more than 40%.
As you can see, H.264 seems to have a slight edge here.
But wait. There's a problem here. Only Opera, Chrome and Safari currently have final versions with native HTML5 video support with either H.264 or WebM support! IE9 and Firefox 4 are both still in beta. We can't just look at total numbers. We need to break down the numbers to specific versions, so that we can see the actual coverage of native video.
When we do this, an interesting picture emerges. Users of certain browsers upgrade much faster than users of other browsers. Someone actually analyzed this, and as you can see, far fewer users of the H.264 browsers run the latest version, compared to the browsers that support WebM.
What does this mean?
Trouble for H.264
It means that the adoption of upgraded versions is a major hurdle for H.264, and those who hoped for IE9 to save the day for the closed codec will be in for a nasty surprise.
If we look at the graphs at StatCounter, it is clear that both Firefox and Chrome experience rapid adoption of the latest version. Within 4 months of its release in January 2010, almost all Firefox users were on version 3.6, and nearly all Chrome users were on version 7 the month after it was released (October 2010).
On the other hand, if we look at the historical adoption rates for IE, they are considerably worse. IE8 was released in March 2009, and it took nearly 10 months for IE8 to overtake IE7!
This means that when Firefox 4 is released with WebM support, most Firefox users will probably be using it within a few months. On the other hand, IE9 is not likely to make a big difference for H.264 until a significant amount of time has passed.
More trouble for H.264
But the bad news for H.264 doesn't end here. You see, IE9 will only be available for Windows Vista and Windows 7. But Windows XP still makes up around 50% of the desktop OS market!
Sure, it is slowly declining, but combined with the slow migration to the latest IE version, this causes even more delays for native H.264 adoption in the browser market.
Possibly even more trouble for H.264
Will the bad news for H.264 ever end? One might perhaps have hoped that this was it, but there's potentially even more.
First some background: Opera, Chrome and Firefox are cross-platform browsers. This means that a lot of things are designed in a way that makes it easy to port them to different platforms. In some cases, this means sacrificing some OS integration. On the other hand, Safari and IE only have to deal with one platform (Safari on Windows doesn't really make much of a difference), so these can easily integrate into the OS of choice. This includes supporting any video codec installed on the system.
So while it might not be possible to add support for native H.264 in Opera, Chrome and Firefox beyond the default codecs in the browsers due to design choices that have to do with cross-platform portability, supporting WebM in Safari on Mac and IE on Windows could be as easy as installing it as a system codec.
Conclusion: The Numbers
As you can see, WebM has a huge advantage when it comes to browser adoption.
IE users are notoriously slow at upgrading, and IE9 will only be available for Windows Vista and Windows 7. Half of all Windows users will not be able to upgrade to IE9!
On the other hand, recent versions of Opera and Chrome already support WebM, users are upgrading to these versions much faster than they are upgrading Safari or IE, and Firefox 4 is likely to be released in the near future, thereby boosting the market share of WebM-supporting browsers to possibly more than 30-40%.
This leaves Safari basically carrying the torch for H.264 with little help from Internet Explorer. Within the next 12-24 months, H.264 might be lucky to have a market share above 10%!
As a final nail in the coffin, IE9 and Safari, being bundled with operating systems, are likely integrated with those operating systems in a way which makes adding WebM support as simple as installing it as a system codec.
The numbers are clear
If we are to trust the numbers from StatCounter, WebM basically owns the desktop browser market, or will, in the near future. H.264 has major problems due to slow uptake of newer versions of supporting browsers, and the fact that half of all Windows users are still on XP will be a major headache to Microsoft and, ironically, Apple.