http://news.cnet.com/8301-10805_3-57371351-75/microsoft-withdraws-one-patent-claim-against-barnes-no...
The claim they're withdrawing is a patent on using tabs like in a browser. I can't even believe the USPTO gave them a patent on this (especially since MS was hardly the first browser to use tabs) but I can see them pulling it from the claim rather than risk having their patent declared invalid.
