Speculating on talent choices that aren't even being publicly tested yet is risky business. Mists of Pandaria isn't in beta testing yet, which means that everything is still be up in the air. What if holy power gets scrapped between now and then? What if the developers decide that shockadins should actually be viable? There are simply too many unknowns when discussing an upcoming game that hasn't faced any public scrutiny.
At the same time, speculating on talent choices with no empirical evidence whatsoever is also fun, because we get to make it up as we go along. I am already imaging a build with the new Pursuit of Justice, where I stack up 5 holy power points via Boundless Conviction and run around with 60% bonus speed for an entire encounter. Will it work with 5 holy power points, or will the speed boost only count 3 of them? Only time will tell. Or Ghostcrawler. But mostly time.