Hmm... I'm a bit confused. The FPS genre is probably the most stagnant of all. Since their beginnings, they've only ever been about shooting stuff with the best graphics possible. I don't think anything has changed at all.
I remember them coming out like crazy back in the Quake 2 days, and every other one used that engine. They were as overdone as those reality TV competition things are today. There were as many good ones coming out then, as there are now.
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No, I don't like anime, Street Fighter, Japanese music or download video game music. Yes, I know, I'm weird.