From Tim and confirmed by the Charleston Daily Mail.
PITCHERS
Stetson Allie
Zack Dodson
Nick Kingham
Zack Von Rosenberg
Zac Fuesser
Matt Benedict
Jordan Cooper
Emmanuel DeLeon
Justin Ennis
Mike Jefferson
Rinku Singh
Trent Stevenson
The first four of those guys will be the main starters, with Fuesser and Benedict fighting it out for the sixth slot.
CATCHERS
Elias Diaz
Jonathan Schwind
INFIELDERS
Jose Osuna
Dan Gamache
Alen Hanson
Kirk Singer
Jodaneli Carvajal
Eric Avila
Chris Lashmet
OUTFIELDERS
Willy Garcia
Gregory Polanco
Josh Bell
Junior Sosa
There's obviously a ton of upside in both the pitching staff and the lineup, but the prominence of likely organizational players, especially among the hitters, is also interesting. Singer (third base) and Lashmet (DH) are currently slated for starting roles, while younger, more interesting players like Carvajal and Avila will start the year on the bench.
Von Rosenberg and Fuesser are back in West Virginia (and so is Dodson, although he missed part of 2011). It looks like the Pirates don't regard Fuesser as much of a prospect, despite strong numbers. Tim notes that the Fuesser/Benedict rotation spot is likely just a placeholder for Ryan Hafner, who's recovering from injury.
In any case, Bell, Kingham, Allie, Hanson, Osuna, Dodson, Garcia and Polanco should make the Power a lot of fun to follow this year.