Yesterday Valve's popular MOBA Dota 2 received a matchmaking update (the details of which can be found here), and the most noteworthy change is that players will have to register a unique phone number in order to play ranked matches from now on.
The motive behind this decision is to try and make it more difficult for people to have multiple accounts, and hopefully stop seasoned players from joining matches below their skill level. Up until May 4 you can still play without registering a phone number, but after that it'll be mandatory.
The update also re-introduces solo queue, which means solo players can choose to only be matched with other solo players.
You can find out more about the update here. How do you feel about registering your phone number?