Basically, I go on the CoD forums a lot and they have a hotfix/title-update thread there where one of the developers posts.
While he was attempting to defend the developers' decision to not buff the 1887 and AA12 nor buff the spas-12 and ksg-12 further, he stated that one of the things the developers use as an indicator of what needs to be buffed is the total KPM (Kills Per Minute) with each weapon.
I pointed out that if KPM is important than clearly the developers noticed how next to no one uses LMGs, which he acknowledged but claimed it was because of the slow movement and lack of long range sightline on most maps. In his argument he gave incorrect data regarding the damage on LMGs, leading me to point out the error he made as well as the numerous ways that LMGs are currently inferior to ARs which was basically everything except ammo and the prone bonus (even the range is worse on LMGs on average than ARs)
As a result of said discussion, the developers decided to buff the LMGs, and indications point to the common theme in said buff being an increase in long range damage.
Here's the title update thread on the CoD forums:
http://community.callofduty.com/thread/100584619?start=0&tstart=0
And the page where the Dev says that the next Title Update will include an LMG buff:
http://community.callofduty.com/thread/100584619?start=5820&tstart=0