Jungle Teemo

I would say he is fun in normals, but not in ranked.

Depends. If you are in Bronze he is perfect. You can do anything in Bronze. When a JG Soraka can 1v5 the enemy team is hilarious.

People have experimented with it a few times. On paper it sounds good, especially when he hits level 6, but in practice....some things are better left on paper.

He's okay. If you're an experienced jungler you can make it work. Take Q first and only gank with red buff. You can probably do either style of damage, just get the blood razor part.

But should I build AP or AD?

he is decent jung. early is a bit meeehh late its decent