• Riot tightened up the rank spread for team matchmaking again. So you have to be within 3 tiers so a Gold 1 and Queue with up to a Plat 1.
• You can select your preferred server, so even though its not guaranteed , you should still experience more consistent ping overall.
• Personal performance no longer matters in immortal or higher ranks. Your elo gain or loss will only be determined by the end result of winning or losing.

You can read the full notes here