Netbooks are already being considered the bright spot in an otherwise tumbling PC industry. In the first quarter of 2009, which roughly corresponds to the quarter Apple reported on Wednesday, worldwide PC shipments totaled 63.4 million, according to IDC. That was down 7.1 percent from a year earlier. Some vendors, including Hewlett-Packard and Acer, saw shipments grow, partly due to sustained demand for netbooks, according to IDC.

Apple doesn't worry about the ebb and flow of PC shipments, but wants to develop a reputation around quality of products, Cook said.

"Cycles come and cycles go," Cook said. "What we are about is making the best computers in the world."