Hate to say you're wrong, but...you're wrong.
Bush's
The 2 wing chairs were famously reupholstered after the first fabric chosen by Laura Bush appeared pink in photos and on TV (Only 2 presidents haven't reupholstered them: Carter and...can't remember).
The 2 couches were custom made for Bush.
The rug was designed by Laura Bush.
The drapes were chosen by Laura Bush.
The Chair Obama is sitting in is the same chair Bush used and was originally designed for JFK.
The paintings are the same however, I would assume, though can't tell from the Obama photo, that new paintings hang on either side of the windows behind the desk are different, since the two in Bush's picture were on lone to him from friends/belonged to him.
The Lamps are the same...really, everything appears to be the same
The only things that traditionally stay are the side chairs and the wing chairs in front of the fireplace (reupholstered); both of which date back to when the West Wing (and current Oval Office) was rebuilt in the early 1930's.
eta: My memory failed me, there have almost always been wing chairs but the 2 in the picture date from the Reagan era.