Yeah, I would expect SL to be updated pretty soon, based on the other sites I read with everyone b*tching about 10.6 messing things up, loosing iTunes libraries, etc.
I guess this build of Flash was current when the whole SL project started,or at least the version that made it to GM. I think Flash just got updated a few months ago.
Regardless, I saw this elsewhere, and reading through the install thread I saw people asking about SL performance on YouTube and Hulu. Putting 2 and 2 together, if you are updating the OS, but downgrading Flash, I wouldn't expect much of an improvement in video streaming.
The article was focused on security, but so far this is not a big issue, just wanted to pass along the article and the video for others who might not have seen it.