I'll take away the obvious one here: mic and webcam support. Other than that, if you ran the Silverlight team, what would your highest priority be for Silverlight v.Next?
Disclaimer: If we get some good responses, I'll pass them along to folks I know on the Silverlight team.
UPDATE: The best place to report Silverlight feature requests now is the UserVoice site: http://silverlight.uservoice.com/