And on the other hand Unreal 2 from 2003 was not using them IIRC, and I felt back hen that it was a missed opportunity and immediately made it look a bit dated with the other cool looking stuff coming out around then.
I remember The Chronicles of Riddick: Escape from Butcher Bay (2004) used them quite a lot. I remember the effect was so obvious that I noticed it despite not knowing what it was or what it was called. Good looking game.
I recall them being hyped up quite a bit in press in prerelease articles about Halo 2 (2004) and TESIV: Oblivion (2006)
Vividly remember my mind being BLOWN by the normal mapping on the prison wall bricks in an Oblivion trailer! Simpler times :)