i'm in the same boat as Testarossa, I really am big on good voice acting. it isn't the decisive factor in whether i like a show or not, but it helps if the voices fit the characters.

I do admit that there are times when I cry for joy at recognizing a certain voice (if the character is similar to a prior one) and other times when i shake my head because the seiyuu can't vary his/her voice enough to make a different kind of character an individual

but i never look at an upcoming show's seiyuu set unless i already know i'm going to watch it for sure (FMA Brotherhood, any Gundam, and, when they do it, the next Berserk anime would be some examples). I do, however, LOVE looking up seiyuus once i'm invested in a show and really enjoying it

i have nothing to say about the "if who is popular now is it because who was popular then or because then was popular then or etc etc..." i was under the impression that how well an anime did depended on A, how the manga / book did B, author reputation (mangaka first, then author, then studio / producer) and C, fanbase mobilization (ads, air time/network, word of mouth) and, of course, the gaggle of intangibles.