From the start, however, the sameness that a fixed pipeline imposed on game engines and their output was apparent. In the early days you could usually tell what GPU a PC game was running on simply by the graphical effects, irrespective of the title or developer.
Change began five years ago with the move from fixed-function GPUs to a new generation that enabled semi-programmability through shaders. Game developers embraced the relative freedom and now they want more.
A fantastic article on the future of real-time graphics techniques, with a number of mini interviews with experts of the field, can be found on the online version of the excellent Edge magazine and is well worth a read for anybody wanting to investigate the upcoming trends in real-time game visuals.
http://www.edge-online.com/features/the-pixel-revolution