Since I'm desperately trying to avoid having to study, here's a list of genin who have cheated/otherwise finished the exam, and those who have not:
The following genin have cheated/finished the exam:
Yasuko (Purple): no cheating, finished test through academic knowledge
Nero (Silverraptor): no cheating, finished test through academic knowledge; passed info to teammates
Matsu Moroha (MageSparrow, godmoded by Moon): cheated, used knowledge provided by Tailed Beast
Tenyama Ryuu (Zersk): no cheating, finished test through academic knowledge
Fuuyama Ayame (Zersk): cheated, used acute sense of hearing to discern written answers off of Ryuu
Ito Kaede (Shades): no cheating, finished test through academic knowledge
Ishida (Innis): no cheating, finished test through academic knowledge
Yua Rin (Callos): cheated, spied on Tomoya via ninjutsu.
Aokigami Yuu (Keveak): cheated, received info from teammate Nero
Kurotou (Fan: this character doesn't seem to be registered anywhere.
): cheated, received info (painfully) from "Momo"
Watanabe Takeshi (Falgorn): cheated, looked for reflections of papers
Sunadou Kyougou (Lord Asmodeus): cheated, increased senses
"Momo"/Rei (not really a genin, but oh well: Callos): cheated, knew answers beforehand
Kita (Shades of Gray): cheated, sneezed in order to peek at Kaede's paper)
The following genin have received test info from their teammates, but have not posted about writing down answers:
Katsurou Fukui (Rebonack, godmoded by Callos)
The following genin have not cheated, or otherwise finished their exams:
Kai Arezawa (Dorizzit)
Raikou Haru (Iceman)
Nara Hari (OverWilliam)
Whee, bookkeeping.