There's been no shortage of cases for Verizon's flavor of the iPhone 4 -- Ballistic, iLuv, iKit, AGF and Scosche have already announced ones of their own -- but if you're looking for a mainstay in the industry, you can now turn to Mophie. The company's life-doubling Juice Pack Air has been ever-so-slightly reengineered to work with both AT&T and Verizon iPhone 4 units, with initial shipments expected by the end of the month. At first it'll ship in black with silver accents, while soft-touch red and glossy white versions are schedu