According to this Variety article Stephen Sommers has indeed been inked as the Director for the upcoming live action G.I. Joe film.
Some plot details have been revealed as well:
Time will tell...Variety wrote:While some remember the character from its gung-ho fighting man '60s incarnation, he's evolved. G.I. Joe is now a Brussels-based outfit that stands for Global Integrated Joint Operating Entity, an international co-ed force of operatives who use hi-tech equipment to battle Cobra, an evil organization headed by a double-crossing Scottish arms dealer. The property is closer in tone to "X-Men" and James Bond than a war film.