403 R St NW is still vacant. It has nice drapes and no mail slot. The front is bricked over so there is little need for upkeep.
Back in 2008 I blogged about this house at the InShaw blog. It was in worse shape then. Now the windows have been repaired and it blends in a bit.
It is not taxed at the vacant rate and doesn't seem to have been taxed at a higher rate for years. It has been owned by Dorothy Farr of Seattle, WA since 2003.
UPDATE 6/16/14: I've been informed that part of the rear of this house has collapsed and is letting in the elements.