By "mutual consent," which is a polite way of saying that "mister Petacchi" accepted his unilateral dismissal with some dignity. [Google translations, anyone?]
Comment away, tho' this is a pretty tired subject. Therapeutic Use Exemption (TUE) abuse is being nipped in the bud, finally. They had to do something, and Petacchi is no better or worse a symbolic whipping boy than anyone else, I suppose. But I hope the blockhead US mainstream media (the ESPNs of the world) don't call this another doping case.