Ummm, this has only been the subject of fifty thousand threads during the last two weeks. Admins, you may fire when ready.
Two thoughts: 1) Anyone else think Mulder's picture came from the liner notes for OK Computer? 2) I think Woody Guthrie's estate is suing JibJab (or maybe JibJab is suing the estate, I'm not sure) over this song. It was made without the permission of the estate, and it could arguably be said that the song isn't a parody of "This Land Is Your Land" (which would be OK copyright-wise, since that would be fair use), but rather a parody of Bush, Kerry, et al. that happens to use "T.L.I.Y.L." (which wouldn't be OK under fair use). Debate and discuss. (This was on Slashdot, but I'd rather see what non-idiots have to say about the subject.) Personally, this is about as gray an area as conceivable, but I'd have to side with the Guthrie estate on this one.
Can't the parody be about both the vehicle (the song) and the subject (Bush and Kerry). Anytime you change up the lyrics aren't you in parody-land? The parody of the two candidates needs no explanation. That thing was really funny. Do you think the music publishers object or do they just want a paycheck?