Figured I'd post this here rather than necro the old threads. Over the last couple of days I went back and played some COD4 and MW2 multiplayer on the 360 to compare against what I'm seeing now in MW3. I owned both of the games for different systems (PC and PS3, respectively) when they were first released but didn't play MP.
First, I was amazed at how the COD4 graphics look when compared to MW3, even though the hardware in the 360 has not changed - it's impressive that the game developers have been able to squeak out ever-improving graphics and performance on the same system.
Second of all, the sound dynamics have improved greatly. For the short time I played it, MW2 sounds like I'm shooing a pellet gun into a tin can. Choppers are different too. Choppers in COD4/MW2 sound like a constant buzz when their machine guns blast, and I have a harder time telling where they're shooting from. MW3 has improved upon both greatly, as I feel like the gunshot sounds are more realistic.
Third, I was surprised at how many newbies are playing both games...way more than I ever run into in MW3. I expected to play against maxed-out 10th prestige players who've been constantly playing the games the last few years, but was pleasantly surprised to be playing against people the same level as me or a bit higher.
Anybody else still go back and play these two games?