For a lot of people, Halo was the literal definition of "next-gen". The Pillar of Autumn was the best opening level to any game I'd ever played (Probably still is). The FPS genre doesn't have a huge amount you can really do with it - it's all gonna be the same old. You run, you shoot stuff. 90% of any extra stuff is gimmicky crap that won't matter if the game itself isn't solid. But Halo did the same old
in a retardedly expert manner, and at the time what it did was so shiny that it was doing new things - it was an FPS on an epic scale. Some popular games are overrated, certainly. And some games really are as good as everyone says. The original Halo is one of these.