Id have to double check the older games but i think tis somewhere like this:
MW1: 10 Days WaW: Few Hours MW2: 38 Days BO: 1 Day (hated that game) MW3: Over 20 Days BO2: 8 Days --- Currently Playing: Borderlands 2 : Maya Lvl 50 It's not until you lose everything that you are free to do anything
MW2: 38 BO1: 25 (+10 or so of private matches) MW3: ~18 (+5 or so of private matches) BO2: 6.
About 2500 hours.
At least I don't have 75+ days in a single one of the games. cough JVEL cough --- http://www.twitch.tv/vraage || GT: v Raage i7-3770K @4.46GHz || GTX 680 FTW 4GB || 8GB 2133MHz || ASUS Maximus V Extreme || SSD 840 250GB || 2TB HDD