Have a look at this chart that best summarizes the state of the tech industry- legally speaking, of course. As you will see, everyone is suing everyone!
http://www.guardian.co.uk/technology/2010/oct/04/microsoft-motorola-android-patent-lawsuit#zoomed-picture
http://www.guardian.co.uk/technology/2010/oct/04/microsoft-motorola-android-patent-lawsuit#zoomed-picture
