The dispute between Japan and Russia is over the southern-most islands in the Kuril Island chain, specifically Iturup, Kunashir, and Shikotan Islands, and the Habomai Rocks. The current dispute dates from the aftermath of WWII when the Allies dictated terms to Germany and Japan. Treaties that reference ownership of the islands include the Yalta Agreement, The San Francisco Treaty, the Potsdam Declaration, and the Treaty of Portsmouth. None of these treaties however seem capable of resolving the dispute. They either fail to describe the specific border, which islands are included or, as is the case with the San Francisco Treaty, the treaty was not signed by both Russia and Japan. The San Francisco Treaty is also the source of the dispute over nearby Sakhalin Island. Reading snippets from some of these treaties and seeing all the problems they cause makes me think I could be a treaty writer.
Though not a new dispute, the Kuril Islands were in the news again on November 1st, 2010 when Russian President Medvedev visited Kunashir Island, the island closest to Japan's undisputed island of Hokkaido. The video I saw on CNN of Medvedev taking pictures of the coastline made him look more like a tourist than a global leader throwing salt in Japan's eyes. The message to Japan was quite clear.
Since Japan is an island nation, The Kuril Islands seem like a natural continuation of its other, undisputed islands. Of course Russia might say that they are the continuation of the Kamchatka Peninsula. Japan is not asking for all of them... only 3 plus some rocks. And since Japan is small and Russia is so big, the part of me that cheers for the underdog wants to say, "come on Russia, show some love."