Hierarch as a replacement for Shaman?

So i was looking for another couple of Judge Foil Noble Hierarchs and i see there at $99 US on starcity, was a wtf moment.

Go to the lgs and ask about the hierarchs massive price jump (judge foil was $40 when i last looked) so apparently she's meant to replace deathrite shaman but i'm not seeing it.

Sure hierarch produce's mana as a 1 drop but i'm thinking BoP make's more sence as a replacement for shamen, shamen and birds allow any color of mana whereas hierarch only gives you a choice of W, U or G.

Bird's, Shaman and Hierarch are all 1 drop for G but if your running Shaman in a mono B neither Birds or Hierarch fit.

Hierarch offer's an exalted bonus but that doesn't replace shaman's other ability's in any way.

So yeah why are people thinking hierarch is the replacement for Shaman?