It shouldn't be confusing, Brwned. Firstly, when I say he plays like Pirlo, I mean like Pirlo I'm talking style. Like Pirlo he was converted from an attacking midfielder into a defensive one. He does his fair bit defensively ( he can actually take care of himself well enough) but it isn't a strength of his game. His passing and work rate is. For my money he is an upgrade of Pirlo.
Furthermore in Brazil, they like their midfielders restricted. That is why the always have trouble fitting in Hernanes. He makes it hard for them to use their favorite tactic of by passing the center midfield in favour of fullbacks and wide playmakers. Because he is a genuine centralised playmaker Pirlo, who likes to dictate play from deep in midfield. Yet is more mobile. Which is why a freer role suits him. Because most Brazilian central midfielders are usually restricted, physical beasts with mainly defensive and destroyer duties, who spend most of the time giving the ball to fullbacks, wide men and forwards, rather than fully utiliising it themselves. And doing the hard running for their teams.
Any way. Check out this link:
http://www.footballingworld.com/2009/02/20/hot-property-hernanes-heading-for-europe-0220/
The article talks about him better than I can.