Oh I saw that in a tweet and I decided to check it, he was actually talking about the length using a harder mode called Heroic. He literally mentioned that it can be 9-11 hours because you would die a lot lol.

I wonder if any real Halo player actually plays the game on anything less then heroic.  

Well it doesn't really matter because the majority of players will play on normal and 5-6 hours campaign is short.

Not sure on that point.  I do not know any Halo players that will play on Normal.  I guess your average casual player will but then again it probably will take them longer than 5-6 hours.  Pretty much all Halo games are about 8 hours for your average joe COD player and since COD is pretty much the same lenght I doubt it will be an issue. 

Anyway from my gaming spear, the majority will be playing Legendary Co-op so we are looking for one hell of a good time.

Well most of a games sales come from casuals and considering how most casuals play multiplayer games a shit ton and are pretty skilled it should also take them 5-6 hours. I've seen casuals play, they're just like us. I think you're just underestimating casuals. I think the only difference is the games we play.

Thos are not casuals. That would be the same as calling SP only players causuals, because they only like one game mode.

This it's actually the first Halo game ever where the MP draws me in. I so look forward to soon be playing war zone, the more that battlefront is sadly missing.

What I consider casuals are gamers who aren't like us, people who don't go onto gaming websites and join the community. They just play whatever game they see on TV or sports games. And a LOT of people play CoDs campaign so that isn't true.

Maybe they're busy playing games instead of talking about scores of games they won't ever buy.

I see what you did there!