Sacry, stop spreading false info:
Yes, the 5-Second Rule is removed. Regen is not "100% all the time" now. As of 4.0, you will generate 100% outside of combat. The second you enter combat, that drops to ZERO unless you are a Discipline or Holy Priest (who gain Meditation as a Passive).
I think that's safe to say 5SR is an outdated mechanic, as well as Meditation doesn't "loose it's meaning"