Stéphane Louge has a blog post that gives some tips for using SP2010 Client Object Model in Silverlight
Source: Stéphane LOUGE's Blog
Through the Client Object Model we can now simply make Silverlight applications or ECMAScript (JavaScript) accessing SharePoint 2010 data without having to develop anything on SharePoint environment (like custom WebServices in SP2007).
NOTE: The blog post is in French