Motorola announced today that its CEO Ed Zander will step down on January 1 and will be replaced by Chief Operating Officer Greg Brown. Zander, who has spent almost four years as head of the mobile device and infrastructure vendor, will continue to serve as Chairman until an annual meeting of shareholders in May 2008.

Zander’s resignation has been perceived by analysts as a direct result of the company’s recent revenue slump and loss of market share. Following initial success with the launch of the popular RAZR handset, Motorola has recently lost out on sales to Nokia and slipped to third in global mobile phone sales, behind Samsung. Motorola shares have lost 24 percent of their value since January 4, when the company first missed forecasts for sales and profit. They rose 37 cents to US$16.02 at 9.39am in New York Stock Exchange trading this morning.