<p>Silverlight v2.0 is getting closer and closer to RTM but I have yet to hear any stats as to how many browsers are running Silverlight. If I ask Adobe (by googling "Flash install base") they're <a href="http://www.adobe.com/products/player_census/flashplayer/version_penetration.html" rel="nofollow noreferrer">only too happy to tell me</a> that 97.7% of browsers are running Flash player 9 or better.</p>

<p>Not that I believe everything I read, but <strong>where are these statistics from Microsoft or some other vendor about Silverlight?</strong> I'm going to be making a technology choice soon and a little bit of empirical evidence would be an asset at this point...</p>

<p>All you Silverlight developers out there, show me your stats!</p>

If you are developing something for a general audience, I would highly recommend against Silverlight as you immediately cut out Linux users.
I went to watch videos for the Olympics (and I run exclusively Linux), and I couldn't watch the video on their site because they were in Silverlight.  On top of that, they actively removed all videos from YouTube, so I had no alternative but to try and scrounge up a Windows boot.  This only served to give me a very negative opinion of NBC, and consider them quite amateurish to pick such a restricting technology for something that should be available for everyone.
While Flash has it's problems, it works fine in Linux, so I would say (at this point), it is a much superior technology choice.
If you KNOW your audience is entirely on Windows (maybe Mac).... then you can consider Silverlight with knowing you won't be cutting out part of your audience.