Rumor has it:
The new beta is "Prime" matchmaking, looks like Valve's taking a page out of the Amazon book for higher quality matchmaking: https://github.com/SteamDatabase/GameTracking/commit/79db109944a71a270e1b5b03440ee18e717dd9d4
Here's the FAQ string that describes its intent:
CS:GO is running an experiment to find out whether players will have a better matchmaking experience when they are matched with players who are using a phone-linked CS:GO account.
To join the experiment, you'll need to upgrade your CS:GO account to Prime status. Just click the UPGRADE button below, which will bind your Steam phone number to your CS:GO account (provided it qualifies, see the F.A.Q. below).
If you own multiple CS:GO accounts, be sure to upgrade your favorite one since you can only upgrade one CS:GO account to Prime status with your qualifying phone number.
Once there are enough Prime accounts, we will begin Prime Account Matchmaking and will start prioritizing matching Prime status players with each other.
There's nothing else you need to do (except convince your friends to click that Upgrade button too so we get enough players to start testing!)
Other points on "Prime":
As with mobile-2 factor authentication on Steam for Android and iOS and Windows Phone (seriously Valve, get on this), VoIP numbers such as the ones used by Google Voice don't qualify
No additional incentives have been confirmed
Remember: "Prime" is an experiment - if it turns out to be a total disaster, or if something else doesn't work out for whatever reason, then Valve could elect to scrap it
Básicamente es una opción que está en fase beta, si mucha gente se une, la mantendrán. Si no, tal vez la desechen. Consiste en darle estatus de principal a tu cuenta si la tienes asociada a un número de teléfono. Con esto el sistema te da prioridad para que te toque jugar con otra gente con cuenta prime y hace que sea más difícil que te toque contra chetos y smurfs.