Have not looked at this recently, but what is the current situation with side-by-side SL 1 and SL 2 installations? A while back I installed SL 2 beta and since then I could never play any SL 1 content. It first wanted me to uninstall SL 2. Really odd since MS did a good job on .Net side-by-side versions, but, at least from my experience, SL side-by-side versions was a no-go.
Ideally the latest SL release should be fully backwards compatible with previous versions (similar to DirectX ).
The reason I ask is because this caused situations where one site wanted me to install SL 1 while another would not work unless I install SL 2. Then when I did uninstall the other version, the one I wanted to install at the time refused to install at all. Just weird stuff like that. I just wonder how many of the "millions and millions" of users that are going to want to watch the Olympics are going to run into similar issues because they might have an incompatible version of SL already installed.