Those videos describe exactly what I am experiencing with this game everyday, very frustrating. I have even started using the riot shield more so I wont have to deal with bullets not hitting people.  The only problem is that it's even worse with this.

Try hitting them with your shield only to have them knife you quickly from behind.  From my view I hit him but then the killcam shows I lunged and missed.  Grrr is all I can say.

hahahahaah thats what im saying.. if you take off theater recording, it should help the lag a little.. but yea i hate getting killed like that.. but i bet someone is saying the same thing about you lol

Holy crap! THIS is why I've been losing my rag over this game and ranting about my general performance. I don't normaly play with theatre / core mode on so don't see the kill cams. This is exactly what I was experiencing but always assumed I was just too slow compared to the other guys. This explains SO much about my general performance. I stopped play core and went to HC instead because at least the bullets are more leathal and you have a better chance of getting the hit in first. Going to check it out tonight, core/theatre mode - suspect I'm suffering from this badly.

Enjoy it while you can. I too was like you in BLOPS. MW3 was flawless for me for one week

now I cannot play for the lag.

You have been warned. Your LAG is on the way

These are not good examples and being shot around corners is a drawback of lag comp and is well documented, although that was an extreme case, it is present in all online FPS's.