In one previous blog I discussed about uploading applications or video asset files to a Silverlight Streaming site (SLS for short). Well, there is a third way of uploading Silverlight XAP files created with Silverlight 2.0 (currently in Beta 1.0). You can find detail on the new method from frog69s' blog titled "Naked XAP upload enabled in Silverlight Streaming" at Windows Live Dev site.
To see how you can create Silverlight 2.0 applications and use the SLS service, check out this example, "Hello World 2.0 for Silverlight Streaming". If you'd like to add images and videos to your application and include them in the xap file, you can easily include them automatically within the IDE. See Katrien's blog on "Different ways for loading images and files in Silverlight 2 applications".