Long Beach, CA
The configuration I'm running IE 10 when this does not work is Windows 8 build 8400. It works with IE 10 with Windows 8 build 9200 and Windows 7 IE 9.
I have been using the build 8400 and 9200 installations as test beds, and the 8400 has been through a lot of things. I may have broken CNN video at one point when I "logged off" of it while it was still playing. (There was an option to logoff that popped up.) I have cleared all caches including cookies, reset IE settings, and reset flash settings to default but it still doesn't work. I guess it doesn't matter much since this installation will go away when Windows 8 is released this week.
But thanks for the responses -- I just thought someone had seen this and perhaps has an answer.