I've been hearing a lot about the challenges that SharePoint will create for eDiscovery.  I say "will create" because while SharePoint content is discoverable and has come up in many cases, the true issues with collecting it have not gotten much press.  Most collection tools are only able to grab SharePoint document libraries (as they are stored on file systems).  However, there are many more content types other than document libraries (e.g. calendar items, task lists, workflows, etc).  It's only a matter of time before the legal community figures out the value of these other content items.