I'm a sad engine watcher a well. Here's some notes I found:
The PW8000 was supposed to be a geared fan section on a PW6000 power core but the PW8000 never went anywhere despite ten years of research and $350 million in development money.
The latest iteration of the geared fan concept from Pratt is their GTF Demonstration program. It is a PW6000 core with a revised planetary gearbox that is alleged to save weight and be more efficient than the stillborn PW8000. Time will tell whether the market will reward P&W's devotion to the geared turbofan concept, or whether it is a technological blind alley for them.
The last time I looked, the big problem as ever was designing a gearbox that can take the loads. Quite some time ago the manufacturers were looking at weird techniques unlike those used in everyday machines. It looks like P&W are using a more conventional arrangement so school's out on whether they can get the wear and failure rates down to manageable proportions.
With regard to RR, I guess the extra shaft partly alleviates the need for other gearing.