Obviously live these things will happen, a few missed notes here and there are cool and expected. It's when there's a LOT of mistakes that I end up being turned off... On the CD, I dont like to hear any notes missed. There's tons of ways to keep the "human element" and be pitch perfect. I dunno, maybe it's just me!
I don't think hes talking about notes dude,he's talking about auto tuning and all that other funny stuff some artists do to sound better, like Bruno Mars etc.