Halo 3 is probably the most disappointing game I have ever played.. Does anyone else agree?

I personally think the 360 games are seriously overpriced. I use a dvd/game rental company to play my games and it is def the way forward. So I received Halo 3 today and was excited about playing it, but how wrong I was. It was boring as hell. Nothing has changed from the first 2 games, which were the reason which I bought my mates Xbox off him. Totally disappointed. Just wondering did anyone else feel the same way?