"If they do continue to support Flash on Windows and Mac, I am hoping they
implement WebM support. That would make things easier for older IE versions
and browsers that do not support WebM to still get support without having to
use H264 encoded files."
There are other ways for people using such browsers to play WebM files
without needing to install proprietary software.
* For Windows Media Player 12 on Windows 7, install the WebM Media Foundation
Components: http://www.webmproject.org/ie/
NOTE: Though the components refer to Internet Explorer 9, installing them
will add system-wide WebM support in applications that use Media Foundation.
* For earlier versions of Windows Media Player, follow the instructions for
installing the WebM DirectShow filters:
http://www.webmproject.org/tools/#directshow_filters
NOTE: As indicated, be sure to also install the Vorbis audio filters.
Finally, there's also a project working to make a WebM decoder implemented in
Java so that you don't have to install third party software.