But you can't get a pure HTML5 DRM experience! All the HTML5 bit is, is a Javascript API to a CDM decryptor that is every bit as crappy, proprietary, closed-source, insecure and buggy as Flash or Silverlight.
I'm still unclear as to how users are supposed to get the CDM decryptors. Are they installed like browser plugins? Or are OS vendors going to provide built-in ones for other companies to use?
Either way, the actual user experience is going to be a pure HTML5 player. If I have to install something first, that's unfortunate, but once it's installed I'll never have to think about it again, unlike the current situation where I'm confronted with the crappy plugin-based user experience every time I use the site.
Currently CDM decryptors are bundled with the browser, which in turn is generally locked to a particular OS or device. Browser vendors don't have to provide a way to install different decryptors and many of them aren't planning to.
Also, the actual user experience is not going to be a pure HTML5 player. Since this is intended to support hardware DRM that overlays the video onto the rendered page itself, sites have to assume the video is basically a rectangle crudely inserted into the page just like with plugins. They might be able to overlay stuff like controls on the top using HTML, but it's not clear if they'll even be able to rely on that.
None of the ones that have shipped already are installed like browser plug-ins. The ones Netflix deploys (PlayReady on Windows 8.1 with IE11 and Widevine on Chrome OS with Chrome) are bundled with operating systems and work with the browsers (one per OS) bundled with those operating systems.
Maybe compared to Flash and Silverlight because they provide much more. But a CDM module would still have to do all the decryption, decoding, rendering, overlaying the browser window stuff. So it would still be a rather large piece of code.
Either way, the actual user experience is going to be a pure HTML5 player. If I have to install something first, that's unfortunate, but once it's installed I'll never have to think about it again, unlike the current situation where I'm confronted with the crappy plugin-based user experience every time I use the site.