The reveal was light on details, though Kingdoms appeared to be a medieval-ish action title. Crytek filed a trademark for "Kingdoms" in April 2009. BOOM video 5403
The game is doubtless powered by Crytek's multi-platform CryEngine 3. The engine's GDC 09 trailer showed a medieval environment similar to Kingdoms.
While Microsoft categorised the game as an Xbox 360 exclusive, it could potentially also be released on PC as the term "exclusive" is here being used to describe titles only hitting one console--Fable 3 was also described as such, despite coming to PC too.