GREG WARREN has been named executive vice president, managing director at MediaVest. Warren will function as the lead relationship manager for advertising and brand agency initiatives. Most recently, he served as senior vice president, managing director, at i4design, where he oversaw strategic design solutions.

JOE BURTON has been named COO/global Microsoft account at McCann Worldgroup San Francisco, a new position. Burton will be responsible for managing Worldgroup’s global operations and financial processes on behalf of Microsoft. Most recently, Burton was COO of OgilvyOne Worldwide and prior to that served as CFO/Global Brands at OgilvyOne Worldwide.

SCOTT SOROKIN has been named as president of Carat Fusion. Most recently, Sorokin was the global account lead at MRM Worldwide overseeing the agency's relationship with Intel Corporation. He was responsible for digital marketing and driving the integration of global marketing programs. Prior to that, Sorokin served as the managing director of Modem Media/Digitas West.

CHUCK BRYMER was named president and CEO of DDB Worldwide while chief creative officer Bob Scarpelli is assuming the additional post of chairman of the agency. Brymer succeeds KEN KAESS, who died on March 27.

Spacedog has promoted DUSTIN CALLIF to managing director, up from director of marketing and business development.

WhenU has named MATTHEW HUNT as chief technology officer and FREDRICK ROLFF as vice president of finance.

ELLEN DRURY has been named senior vice president, director of local TV and radio investments at Optimedia. She succeeds LINDA PITTMAN, who left the company. Most recently, Drury served as a media consultant. Prior to that, she worked for MediaVest.

JOEL RODRIGUEZ has joined Fallon Minneapolis as a group creative director. Rodriguez most recently worked at TBWA/Chiat/Day, New York, where he was a creative director. Prior to that, he was an associate creative director at BBDO, New York.