It's a good thing indeed that the Pirates have two players in Andrew McCutchen and Garrett Jones who could legitimately fit into the N.L. Rookie of the Year discussion. Unfortunately, I don't think they'll make it past the first round. As pretty much everyone here knows, I'm not overly high on Jones' long-term potential, but his performance so far has been indisputable. Unfortunately, he's only played in 45 games, which isn't, and shouldn't be, long enough to make an impression on most voters. It's extremely hard to sustain a .982 OPS over a long period, and Jones isn't a great bet to do it. Just ask the Brewers' Casey McGehee, who had a .963 OPS after 47 games this year but has slowly faded into the background since then. Like Jones, McGehee is an older minor league veteran getting a fresh start with a new team. Also like Jones, McGehee has a long history of posting minor league OPSes in the 700s. McGehee certainly shouldn't be a top candidate for Rookie of the Year honors, and barring a very strong second act that I don't really see coming, I don't think Jones will be either.
This isn't to dismiss Jones' season outright, however. It's probably reached the point where he's done enough to warrant adjusting our (well, at least my) expectations upward a bit. There are occasionally players who have unimpressive minor league performances and reach the majors late, but still manage to have decent careers--I think of Eric Byrnes here, or Bill Hall. But both Byrnes and Hall had short and rather strange peaks, and hoping for Jones to reach even those players' rather un-lofty heights is probably hoping for too much.
McCutchen is a different story, and if he played with a team that got more media attention, he might be a legitimate candidate. But his stats, at least the ones the voters are likely to see, are good but don't jump off the page. A lot of our excitement about him stems from his blinding speed on the bases (which is cool but ultimately not that important) and from his excellent defense (which really is important). Neither of those are likely to get a lot of play with voters.
I think the N.L. Rookie of the Year is pretty likely to be the Braves' Tommy Hanson, who comes with a top prospect pedigree and has a 9-2 record. I'm not as impressed with Hanson as some are; he throws hard and has good breaking stuff, but his fastball is pretty straight and he leaves a lot of balls up, which I think could catch up with him. Still, he seems to be the favorite, and if he falters, J.A. Happ of the Phillies and Randy Wells of the Cubs are probably next in the queue. It's possible Dexter Fowler of the Rockies could enter the conversation, too. It will be tough, in my view, for McCutchen or Jones to pass all these guys. McCutchen is probably the most promising of all of them (although you could also make a case for Fowler, who I think could become something like a better version of Corey Hart, or for Hanson). I'll take potential over an award any day, unless it's a World Series trophy.