My colleague Tim Heuer, posted a great example of how you might extent Expression Encoder to encode and upload content to a Content Delivery Networks (CDN).  If you've used the Expression Encoder add-in for Silverlight Streaming, you've seen an example of this type of extension.  I could envision a plug-in that would use FTP to upload to any hosted server (LAMP or IIS).

If you want to see my recorded webcast on Silverlight for CDNs, go here.