First up: Kevin Goldstein of Baseball Prospectus. His list has three Pirates. Andrew McCutchen is #24, Steve Pearce is #43, and Neil Walker is #94. The second ranking, posted a few hours later, was Keith Law's for ESPN.com. He ranked McCutchen at #12, Neil Walker at #89, and Brad Lincoln at #97. His ranking included comments, which I've provided below:
McCutchen started off horribly in AA this year, but finally turned his season around in his last 40-odd games there, hitting .307/.382/.460 from July 1 until a mid-August promotion to AAA. McCutchen has incredibly quick wrists that give him tremendous plate coverage and result in a lot of hard, line-drive contact, as well as flashes of raw power. The player-development fiasco in the Pirates' minor league system under Dave Littlefield has hurt McCutchen, however, as he doesn't use his lower half and get his weight transferred with his swing, so all his power now is in his wrists and forearms; once he gets his whole body involved, he should have 30-plus homer power. He's a 65-70 runner with good baserunning instincts, and he plays a plus center field. Take heart, Pirate fans: Nyjer Morgan's goofy routes have only a year or so left in Pittsburgh's center field.
[...]
Walker's plate discipline took a 180 for the better this year, to the point where he's now clearly going to play in the big leagues. He wears down every season even now that he's no longer a catcher, and his defense at third remains unacceptable, so he may end up a 'tweener who doesn't hit enough to play first and can't handle any tougher position on defense.
[...]
Lincoln missed 2007 after Tommy John surgery, but is expected to be ready to go in March. He has an above-average fastball and power curve with some feel for a changeup and is a good athlete who can swing the bat a little bit. It remains to be seen whether his stuff still measures up after the operation.
The third list, compiled by "20 members of the scouting community", was posted at minorleaguebaseball.com. It includes only one Pirate, Cutch, but gives him his highest rating among the three lists, at #8 overall. The article links to a little analytical capsule. I'd quote it here, but you really ought to click the link because the page also includes some scouting video that's worth seeing.
It's interesting to look at the lists as a reflection of the preferences of the men who wrote them and the institutions that commissioned them. Goldstein spent most of his career at scouting-oriented Baseball America, before moving to the much more stat-oriented Baseball Prospectus. Law is a writer who started out at BPro, spent some time in the front office of the Toronto Blue Jays (under J.P. Ricciardi, the least "Moneyball" of Beane's assistants), and then took a position with the more scouting-oriented ESPN. The scouts, meanwhile, are going to be fairly scouty in their perspective, but their list is the process of analysis-by-committee rather than individual insight, which can be an advantage at times (because it rules out individual craziness) and a disadvantage at others (because it rules out individual brilliance).
The link between respect for scouting and enthusiasm over McCutchen seems pretty straightforward. He didn't have the killer offensive season that some other top CF prospects did last year, but most scouts seem to retain confidence in his tools and makeup, and they feel that his second-half improvement is a reflection of adjustments that he made (instead of random variation, or promotion bias, or something to that effect). Looking at the video, I do think that Law's point about McCutchen's lower body is a good one. With better weight transfer, he could add some extra pop, though I think that if it does show up it'll come initially as doubles/triples rather than HR. He just looks like he's got a line drive swing right now.
It's interesting that Law didn't put Pearce on his list at all, especially when Goldstein ranked him so highly. There are a lot of valid reasons why he might have done so, but I'm curious about which ones apply here. I dropped him a note, and if he replies, I'll be sure to pass it on. It's also worth noting that BPro has generally treated corner players with unusual bodies (Pearce is kind of small) better than most analysts in the field.
I think it's very interesting that there seems to be a good consensus about Walker, placing him as a future starter but not a star. That might be a disappointment for casual fans who wanted a star, but if he turns into a Travis Fryman or a Doug DeCinces, it's honestly not a bad outcome for us. An average regular would be an upgrade on what Bautista's giving us right now, and when you have an average regular making the minimum, that lets you throw extra money at other holes.
There are still a few lists out there lurking in the weeds, most notably the one from Baseball America, which usually comes out in late February.