Amid criticism over the company's shortcomings and a much weaker position in the mobile phone market, Motorola CEO Ed Zander will step down at the end of the year.

The change would take effect on January 1, according to a statement from the company. Zander would be replaced by current president and chief operating officer Greg Brown, who joined the company in 2003. He would stay as chairman until the shareholder meeting in March of next year, and serve in an advisory role through January 2009.

Zander had received much of the criticism for the company's faltering business, although he maintains that it was his own decision to leave and that he was not pushed out. Some shareholders had previously been calling for his ouster.

"This is the right time for me to move on to the next phase in my life and spend more time with my family. I am grateful I had the opportunity to lead Motorola over the last four years. It's been a wonderful experience," he said in a statement.

Following the company's highly successful RAZR product, Motorola's sales slowed as it was unable to find a successful follow-up to the phone. Making matters worse, the company had made the decision to make less money on each phone in an effort to increase it's market share.

So far, that hasn't worked. The company is now third in sales behind Nokia and Samsung, and a 36% plunge in mobile phone revenue. Overall, profit dropped some 94% year-over-year.

It's not immediately clear how Brown plans to change things at Motorola. However, he did tell the Associated Press in an interview that he would provide an update on restructuring the company early next year.

Brown previously had worked at Micro Muse, which is now part of IBM's Tivoli network management tools. His background in enterprise networking could benefit the company, say analysts, as that sector of Motorola's business has shown the most growth recently.

"It will be imperative to have at the helm someone that understands the nature and fundamental importance of an enterprise networking business to a large network equipment player; Moto may find this in Brown," Forrester analyst Chris Silva said. "This leadership change may point Motorola in the right direction to take on Ubiquitous Mobility."