Infinity Ward makes fun games that are way out of balance and have many problems (the key point being they are fun though)
Treyarch makes super balanced games that are slow paced and boring (PS Treyarch killed sniping)
After BO released I was on the Treyarch bandwagon but now I'm just totally sick of BO because even though its balanced its boring as hell unless you're with a full party and you can destroy your opponents. I say IW makes the better games because even though they're screwed up and unbalanced at least they're very fun.
All IW has to do to make MW2 easily playable again are:
- Patch OMA and scavengers so they don't restock grenade launchers
- Patch commando to massively reduce lunge range
- Take tac insertions out of FFA to get rid of boosters (yes, sadly there are still boosters)
- Patch the blast shield so it doesn't give you tunnel vision and hide your radar (thus making it usable) so you can actually have a defence against danger close noob tubes/grenades
- Patch the glitch for getting on top of highrise
If they could do all that it would make their game amazing.
