Did you see the Showcase? http://silverlight.net/showcase/
The newest samples show up there.
All I see with Silverlight is numerous sites trying to imitate You-Tube. If you're not in the video redistribution business there seems little point.
I clicked on the SQL Server 2008 "showcase" site using my 4 grand Dell Vista laptop and my supposedly 8MB broadband on a Saturday morning when things are relatively quiet. All I got was broken jittery speech and lockups, culminating when the thing finally finished stuttering its way through a lacklustre set of stills the message "Error code: 4001. Media Error. AG_E_NETWORK_ERROR". I don't think I've ever seen anything approaching that with that level of incompetence with the "rival" Flash product!
I'm afraid it all smacks of the whole mobile phone technology of a few years ago (My memory's so bad I've forgotten the name already - was it WARP?).
Not seen anything yet that says "If you're not in trying to sell movies/TV over the web" you need to see Silverlight.
Went to see "Silverlight on the big Screen" in Dublin with three colleagues from work last week and all the folks I went with came away with the same "underwhelmed" impression (didn't help that it had been hyped as a "big screen" experience with a member of the Silverlight team when what we got were some pretty ropey demo's and PowerPoint slides projected onto a small section of a cinema screen by someone who came across as a marketeer rather than a developer).
When 1.1's out (my guess is May next year at the earliest) then things may start to get interesting, but in the meantime unless you argue that it's an easy way to start getting into WPF (by learning WPF "lite" first via Silverlight) there's way too much other stuff to get to grips with that seems way more relevant and usable in the real world.
And I got my first view of Channel 8 through following the MixUK showcase link - man, I know times have changed but even in my day of doing Computer Science with punched cards and paper tape when we were all pretty nerdish it would have been hard to find two student "presenters" less well prepared for the task given to them. Was the first requirement "Have you had a personality bypass and look like a deer trapped in headlights whenever someone points a video camera at you?". Sure seemed like it. I had to stop the "interview" with Guthrie 2 minutes in because I just wanted to curl up and die (or, as a Brit, email the man an apology that his precious time had been so wasted). It's hard for anybody to make a Guthrie interview dull, tedious and body squirming but that "showcase" certainly did it.