Just like Arceus, how I used to say "Ar-seeus" before watching The Jewel of Life, now I must correct my way of saying Unova.
All of my friends and I pronounce it "Uh-no-vah", or "Ah-no-va," but seeing as how apparently the anime pronounces it "You-no-va" I must force myself to change it (I can't stand being considered to be in the wrong...)
I really don't know, I don't watch the anime anymore, as IMO the quality has dropped, but I still watch the movies (those are still excellent).