Yep, he wore black during this morning’s presentation at Macworld in SF and introduced the stuff that had been expected - an ultra-thin laptop computer dubbed the Macbook Air and an online movie rental service for iTunes. He also reported that 4 million iPhones have been sold, which gives Apple almost 20 percent of the U.S. Smartphone market (Blackberry is at 39 percent). But apparently there were no big surprises, which is often what happens at Macworlds (and probably explains why the stock is way down). Here's more from Barron's tech guy Eric Savitz, who blogs at Tech Trader Daily.