Silverlight 2 has now been RTM'd.  Here is a quick overview of whats new in Silverlight 2.

• Text Rendering - a lot of improvements went into overall text rendering.  This is an area that we will continue to improve and focus efforts.  The Portable User Interface font (default font if no FontFamily value is provided) looks a heck of a lot better in my opinion.
• Controls - Read Shawn's post about the new controls
• Networking - The ability to call secure (SSL) services from a non-secure hosted Silverlight XAP.  The only caveat is the new service endpoint must specify a policy via clientaccesspolicy.xml at the root of the endpoint domain.  Once this is in place (at the root of the endpoint domain), your XAP hosted in a non-secure SSL HTTP instance can call an HTTPS-based service.
• ADO.NET Services - Finally made it in!

 Some links to download:

• Silverlight Tools for Visual Studio 2008
• Silverlight 2 Developer Runtime (Windows)
• Silverlight 2 Developer Runtime (Mac)
• Silverlight 2 SDK offline documentation (CHM) 
• Blend 2 SP1

Host of other good information about the release - Recommend reading the official release here.