ScottGu dropping the news as usual. Most interesting feature, IMO, is the upgraded communication support:
"The next Silverlight preview release will add support for REST, POX, RSS, and WS* communication. It will also add support for cross domain network access (so that Silverlight clients can access resources and data from any trusted source on the web)."
Of course, even more importantly, Silverlight will have much better support for building UI with actual textboxes, checkboxes, etc. that were left out of 1.0... but that's old news.
[1] http://weblogs.asp.net/scottgu/archive/2007/11/29/net-web-product-roadmap-asp-net-silverlight-iis7.aspx