Are you for real?
Did you really expect something diferent from the previous Halo games?
That Halo 3 would reinvent the FPS genre?
Halo 3 is a great game, if you look at it for what it is, the ending of a trilogy, and with that in mind, it works very good.
I play a hell of a lot of FPS, i played Halo for the 1st time 5 months ago (and then the 2nd and then the 3rs), i play a lot of PC FPS (more than console´s), i´m not 14 and i don´t like the shout racism slogans (i don´t use voice when online), so, i´m not in your stereotype, but i´m a Halo fan.
Halo doesn´t have the best story in the book, don´t have the best gameplay ever, but it works as a trilogy.