is powering an ATmega386P with usb cable and USB AC Charger plug save?

Yeah keep in mind some USB AC chargers can put out more than 500mA, my Motorola Droid Bionic's charger claims 850mA, my old Blackberry AC charger claims 700mA... I think the Apple iPad charger can push 2.1A (and it's 5.1V I believe?)