It could possibly, but the site should use a common 'standard' media plugin, such as QuickTime, Flash, or even RealPlayer (ugh).

Not some obscure media plugin nobody has ever heard about.

Just to add another thought. I haven't been around a PC virus for a long time (the only PC's I work with are very well maintained). What do they do these days? I know a lot of them are just mules for spammer bots, but are there still ones out there that just destroy your hard drive for kicks and giggles? I mean honestly, with how hard it is to defeat security these days, it seems like you'd need to put some money into any bug you create...so there'd have to be some cash based reason for doing this, right?