He can score well but that's not the draw here. Anyone talented enough who works hard enough will score with the team we have. It's his defensive game that I'd be interested in. From what I've seen and from everything Avs fans have said, he's a Selke caliber player. The games I've seen him play, more than just a few, indicate to me he's a hard worker and is competitive as hell. He blocks shots, is a great PKer and can steal pucks fairly well.
My only concern would be can he play wing? We have plenty of centers as is and I wouldn't trade Flip for this guy. I would however give them Nyquist, even though I think Nyquist has a higher offensive upside. O'Reilly completely skipped the AHL and didn't look out of place, we know what we'd be getting and he's basically a slight variation of Flip from what I've seen and heard. Just a little faster but with less defensive prowess. I don't want to give up Nyquist but I dunno what else they'd want. If we could give them Sheahan and a second I'd be pretty pleased.
As I said, I've seen this guy play a lot. Defensively he's as good as Flip or Helm, works hard, back checks, plays physical for his size, has real good speed. Offensively you're talking about a guy who put up 55 pts. in his second year, so I don't know if Nyquist really does have more upside. Especially considering O'Reilly has better size and strength and is still developing his game at the NHL level as well.
I doubt he could transition to the wing though he seems like a Jordin Staal type center, big strong puck carrier who likes to gain the zone and then dish. But we all know Zetterberg definitely can play the wing effectively.