I miss CoD4's perks, aka having rocket launchers and stuff as a perk so it wouldn't clog up the weapons. I also miss the snipers because all i got in MW2 and Black ops were stuffty ones.
Me and my friends have a tradtion of always playing CoD4 at my sleepover because it never gets old.
MW2 was unbalanced and fanboys spread like wild fire and Black ops was a nice thing to see and I liked the other gamemodes but I miss the lack of shotguns and snipers.