The proc frequency changes based on the ilvl of the trinket:
541 ilevel = 112.88% proc multiplier
535 ilevel = 106.74% proc multiplier
528 ilevel = 100.00% proc multiplier
522 ilevel = 94.56% proc multiplier
502 ilevel = 78.49% proc multiplier
463 ilevel = 54.57% proc multiplier
This counts for both Unerring Vision and Rune of Re-Origination.
Well this is interesting. But it aint additional, so basicly 528 stays the same and everything below is nerfed while heroic are buffed?