Yes. Second instruction doesn't apply to "stock" SM, but if you replace SM's av .dll's with @roytam1's modded ones, it probably does. So to be safe, I set both media.wmf.enabled and media.ffvpx.enabled to false for testing.
With those settings, it appears SM works the same on Win 7 as on XP. Despite appearances, Primetime does work, but for whatever reason, it just won't appear in the list of plug-ins!