im inclined to disagree here. i thought the same as this article when i played GoW1... but after playing 2, i surmise that the locust are in fact humans of the same planet transmogrified by emulsion poisoning. if u read the notes scattered about about the "sickness" spreading, u take into account the stasis tube creations and the fact that emulsion transforms anything it comes into contact with, its pretty obvious that the people of jacinto are turning into locusts and marcus' father is somehow involved with the experimentation along with the locust queen. as a side note its possible that the locusts are the ex hmans and its possible the emulsion locusts are the true inhabitants :)
bein devils advocate here... maybe expectin too much after the phenominal freedom frighters... but stormed thru it in 5 hours and found the 2 endings unfulfilling and anti climactic, i had to reset three times after being absorbed into a wall, and got killed well into double figures the amount of times i was killed whil TOTALLY in cover (when i could get into it) and as for the amountof times ive seen my comrades watching my lifeless body slowly die... 5/10 for me