In the last CS:GO thread there talk about the match making system and what the CS:GO team at valve do in order to try improve the system.
Very recently (roughly 2 days ago) the CS:GO development team went live with a new matching system to replace their previous Prime Matchmaking. They found Prime to have created a bit of an artificial divide between players that contributed to otherwise well matched players being unable to be matched together.
So the team rejigged their Prime service to remove this artifical divide and incorperate a range of other measures that improve the match making experience and may help improve the filtering out of cheaters.
The system is developed in such a way so that it potentially rates toxic players as less trustworthy (measured by player-player interactions) and may slightly improve that toxic atmosphere that is the bane of CS since its inception.