@junglers where do u gank first?

If I'm ganking directly after the 2nd buff, usually whichever I'm closer to that looks like it'd lead to a sucssful gank (soooo mid/top or mid/bot, whichever is more gankable).

the lane where the enemy is pushed to our turret.

the lane that has no escape, ie velkoz

the lane that is winning hard, ie 3-0 top lane, up 20cs? GANK AGAIN, super deny the enemy top laner.

depends entirly on matchups and "gameflow".

If there´s a high snowbally champ like Irelia in the game you usually should focus on that lane first - getting your Irelia a fast kill can already win the game for you, especially if you return immediatlly to prevent a retaliation dive. If an opponent lane overextends...just go there, at least you take some pressure of your laner. If you have a strong duelling jungler (or nunu) you can just go for the opponent jungle if no immediate target shows itself. There´s nothing more harmfull to jungling then being inflexible, you have to be able to read the game and act fast.