@Whiners: Stop complaining about Nasus. He is balanced.
Wanna know how you beat a Nasus in lane? Punish him every time he wants to last-hit. Every time he goes to farm a minion, attack him. Take advantage of his attack animation wind-up and recovery, and hit him when he can't attack back. Harass him or even engage on him early on, and if you either kill him early or force him to recall early, he'll be seriously hurting.
Good lane counterpicks:

Wanna know how you beat Nasus later on? Make it so that he has to spread his attacks amongst your entire team. As long as he can't land a killing blow, your team can kite him to death easily. Also make use of crowd control-cycling even if he got Tenacity. Don't EVER fight him solo, or you probably deserve to die.
Good team counterpicks:

Bottom line, stop trying to get Nasus nerfed in high-tier play. HE IS BALANCED.