OK... just watched it.
I think it was a very good show, loaded with vibrant imagery of our world. But I would rate Koyaanisqatsi far far above it. Many of the scenes in Baraka are almost identical to Koyaanisqatsi, some are (possibly intentionally) blatant ripoffs of scenes in the -qatsi trilogy. I'd call it Koyaanisqatsi for people who don't like Philip Glass.
As similar as it is to Koyaanisqatsi, though, I feel it lacked much of the power that Godfrey Reggio's work embodied. While the -qatsi films provoke deep introspection about who we are & what we do with & to our world, Baraka just gave me a kind of... "Oh." response.
So if you haven't seen either Baraka or Koyaanisqatsi and plan to see them both someday, then watch Baraka first. Otherwise just watch Koyaanisqatsi & skip Baraka.
Just my opinion though