I think Rory will maintain his number 1 ranking, but I also think that it will take a few tournaments to dial in the new gear. At the level that these guys are playing, with thier swings so precise, the gear does make a difference. Just like a Stradivarius sounds different than an Amati to a concert violinist.
You can use the most sophisticated forging techniques, and shape the irons very precisely, but ultimately, the guy swinging the club has to feel it and believe it or he's slamming that trunk Friday afternoon. And the putter has to be right as well. That Method putter is already in the closet along with his old Titleist sticks!