Yes, BRINK uses OpenGL, not DirectX.
idtech4 is openGL
as it apears most people here have no idea why that is an answer. openGL is the open source competitor to direct X, instead of being saddled with which direct x level the game is it's saddled with which openGL level your video drivers are.
so when brink launches you WILL have to update your video card drivers or else the game will potentially not work at all. openGL is updated far more frequently and is cutomisable per game to have new features. it means new video card features make it to consumers faster. and all shader model 5 (directx11) features are available to all platforms as long as the hardware is sm5 (ps3 is sm3, xbox 360 is sm3.5, pc ranges from sm2-5, brink appears to be using 3+ so update your video cards you cheapskates.
sadly however openGL is not as robust as direct x, if a feature is not supported by the hardware renderer, it tends to continue trying to render it via software, usually this results in extreme slowdown or outright crash to desktop. UPDATE DRIVERS.
the anti microsoft brigade all love openGL, at least the theory of it, personally i think direct x is faster and far more reliable as a bad video driver wont make it completely unusable. but it's worked for Id for over a decade so what do i know.