We have the official press release for the just-revealed XCOM: Enemy  Unknown, which offers a few more details on what to expect from the new  game:, which was 
revealed earlier today:
New  York, NY – January 5, 2012–2K Games announced today that Firaxis Games,  the creative team behind the iconic Sid Meier’s Civilization®  franchise, is developing XCOM: Enemy Unknown, an action strategy title  that is planned for release in fall 2012. XCOM: Enemy Unknown will be  instantly recognizable to fans of the original X-COM, while breaking new  ground in strategy games for today’s console and Windows PC gamers.  With equal emphasis on deep strategy and intense tactical combat, XCOM:  Enemy Unknown will place players in control of a secret paramilitary  organization called XCOM. As the XCOM commander, players will defend  against a terrifying global alien invasion by managing resources,  advancing technologies, and overseeing combat strategies and individual  unit tactics.
“We’re looking forward to building upon the core gameplay experiences  that fans of the original X-COM love, while introducing the franchise to  a new generation,” said Sarah Anderson, senior vice president of  marketing for 2K. “With Firaxis’ XCOM: Enemy Unknown and 2K Marin’s  upcoming XCOM, 2K Games will be offering two different gameplay  experiences drawing from the classic X-COM universe. Each game offers a  unique XCOM experience in different genres, as envisioned by two  different studios with unique creative visions.”
Released in 1993, the original X-COM is widely regarded as one of the  best games ever made and has now been re-imagined by the strategy  experts at Firaxis Games. XCOM: Enemy Unknown will expand on that legacy  with an entirely new invasion story, enemies and technologies to fight  aliens and defend Earth. Players will control the fate of the human race  through researching alien technologies, creating and managing a fully  operational base, planning combat missions and controlling soldier  movement in battle. 
“It’s been a dream of ours to recreate X-COM with our unique creative  vision. We’re huge fans of the original game and it’s a once in a  lifetime opportunity to re-envision a game that is as beloved as X-COM,”  said Steve Martin, president of Firaxis Games. “We were careful to keep  XCOM: Enemy Unknown true to the elements that made X-COM such a revered  game while delivering an entirely new story and gameplay experience for  both die-hard X-COM fans and newcomers to the franchise.”