So basically a thread to list Superman (and some stuff focusing on his villains) issues/appearances that you find "key" in new52 version that seams to be wrapping up.
Mine:
Superman: 45-47, 23.1 Bizzaro, 23.4 Parasite, DC Sneak Peek - Superman
Action: 0-18, 25-30, 35-44, Annual #1, 23.3 Lex Luthor, 23.4 Metallo, Action Comics - Futures End #1, DC Sneak Peek - Action Comics
Batman/Superman: 1-4, 10, 16-20, 28-30
Grayson Annual #2
Swamp Thing #20
Forever Evil - for Luthor/Bizzaro/Ultraman and not Superman himself.
Obviously I haven't read everything and I might be missing something obvious here.