Local building codes specify how many nails or screws you should use to hang drywall and in what sort of pattern. Codes vary not only from region to region, but from room to room; for example, more fasteners may be required in bathrooms. Check with your building department.
Many professionals don't nail in pairs, but there is good reason to do so: If one nail pops through the paper, the other will hold.
For ceiling panels, the general practice is to pair nails at 12-inch intervals around the perimeter and 12 inches along each joist. Requirements are less stringent for walls. If you don't use adhesive, install two nails into the wall studs at 16-inch intervals and a single nail every 7 inches along edges. When using adhesive, install two nails at 24-inch intervals and one nail at 7 inches along the edge. Keep adhesive 6 inches away from top and bottom of sheet.
On November 19, 2010