Top 15 eroge of 2012 according to 2ch's eroge neta/industry board

#1 Hatsuyuki Sakura
#2 Ourai no Gahkthun
#3 Kono Oozora ni, Tsubasa wo Hirogete
#4 Venus Blood Frontier
#5 Tsuki ni Yorisou Otome no Sahou
#6 Harumade, Kururu
#7 Soukoku no Arterial
#8 Dracu-Riot
#9 Grisaia no Meikyuu
#10 Rance Quest Magnum
#11 Furuiro Meikyuu Rondo
#12 Re:birth colony -Lost azurite-
#13 Owaru Sekai to Birthday
#14 Witch's Garden
#15 Irotoridori no Hikari

Source, with numbers and such: http://asitagamienai.blog118.fc2.com/blog-entry-1808.html