The Pirates have assigned shortstops Brian Friday and Argenis Diaz, outfielders Brandon Jones and Gorkys Hernandez, and pitchers Ramon Aguero and Ronald Uviedo to the minors. No huge surprises there; I thought Jones might get a slightly more serious look as a backup outfielder, but the Pirates have a ton of possibilities there and Jones has an option left. Jones, Friday and Diaz will probably all be at Indianapolis. Aguero and Uviedo will be the key guys to watch out of Altoona's bullpen, and the P-G post now also notes that Hernandez was sent to Altoona as well.
...And while I'm linking to the Post-Gazette, you should check out their story on Starling Marte if you haven't already.