Goalkeepers: Nicolas Navarro (Napoli), Mariano Barbosa (Free Agent; ex-Banfield and Villarreal), Mariano Andujar (Estudiantes; very complicated).
Defenders: Nicolas Spolli (Newell's), Sebastian Dominguez (America; coached by Simeone in Estudiantes), Facundo Quiroga (Wolfsburg), Juan Pablo Sorin (Hamburg; would be a target if Villagra leaves).
Midfielders: Ignacio Piatti (Gimnasia LP; a business group wants to buy him and loan him to us), Diego Barrado (owned by River and returning from a loan with Olimpo; Simeone is said to be interested in his services).
Forwards: Santiago Salcedo (Newell's).
Mario Yepes's name is also floating around a bit, and the Colombian himself even expressed his interest in returning. Either way, I don't see him arriving anytime soon..
As for players out:
Goalkeepers: Juan Pablo Carrizo (to Lazio), Juan Marcelo Ojeda (unknown destination; highly likely to be transferred if another goalkeeper arrives).
Defenders: Cristian Nasuti (unknown destination - wanted by a few Mexican clubs and Godoy Cruz; fed up with being a "back-up" player), Danilo Gerlo (wanted by Asteras Trípoli of Greece).
Midfielders: Oscar Ahumada (hasn't renewed his soon-to-be-expired-contract yet), Rene Lima (to PAOK FC of Greece on loan), Diego Barrado (if Simeone decides to not use him, Godoy Cruz and a few other "small" clubs are interested in acquiring the midfielder on loan), Nicolas Domingo (wanted by Atlas of Mexico), Rubens Sambueza (his loan with Pumas will finish, but his future remains in the Mexican league with a different club next season).
Forwards: Sebastian Abreu (to Beitar Jerusalem), Alexis Sanchez (returning to Udinese from his loan with River).