I dislike CoD simply because I simply just... dislike it. Mainly because there are small maps, everyone is running around quickscoping in close quarters combat, and the fucking killstreaks man.. don't get me started on them.. dumbest shit ever made.. that fucking choppergunner.. I seriously wanna slice the dudes head of that thought of that idea.

CoD 4 however was fantastic playing on pc with promod servers!.. Played that for aaages! but after CoD4.. imo, it has literally been complete and utter shit..

I've enjoyed Battlefield since BF1942 (LOL at people thinking bf1943 on console is the first BF game). I haven't played all of the expansion packs, but I still own 1942, 2142, BF2, played BF Vietman (The BF2 expansion, NOT the bfbc2 expansion). and BC2, Didn't have xbox when BC1 was out.
And I can honestly say, the CoD games with the exception of CoD4, Have never been as much fun playing as I have had in Battlefield. Don't have that much experience playing with friends in a squad until BC2, but playing alone sure is great fun as well.. just not as much fun.

The freedom in BF is also something I really enjoy. Like the vehicles, 64 player servers etc etc the list goes on.

This is why I choose BF over CoD any day!