apparently so
This has been driving me nuts, so I tried on Linux/firefox with user agent switcher, no matter what OS/browser combo I tried these sites simply wouldn't load flash video. I didn't get any error messages.
In chromium I got the 'flash is too old' error and on the first try was given the option of 'run flash this time only' which would play the videos. If I chose not to play, no amount of reloading would give me the option to play 'once' until I cleared cookies.
Then I booted into the XP and Vista instances on the same 2 computers, made sure IE, the OS and flash were the absolute latest and the same sites still wouldn't play.
These are both laptops, but vastly different hardware so I can't imagine that's an issue. I have one more machine to test this on, except there's no windows available on that hdw.