Okay, now I'm a bit more inclined to believe the guys at Microsoft are serious about this stuff. An MS press release has announced they're working with the Mono guys to deliver Silverlight for Linux:
In addition, Microsoft will work with Novell Inc. to deliver Silverlight support for Linux, called Moonlight, and based on the project started on mono-project.com.
Sure, like Chris Koenig pointed out to me when I asked about Linux support, Linux's desktop share is tiny. But there is a disproportionately high number of developers in that tiny share, and we're pretty vocal. :)
Working with Novell is an easy way to get going on this -- and the Linux support shows they're serious about competing with Adobe in this space.