There have been a few smaller changes on the server side. Post-game ladder rating change is now a 50:50 weighted average between the smoothed WHR change and the change that one would get from classical Elo. This means that the ladder rating will still converge towards the 30 day WHR average, but there will be a higher minimum gain/loss for balanced games.
The following commands are now available to all players in custom hosts with less than 8 players. They don't have any effect if there are more than 8 players. You can use these commands to create battles for players of a specific skill level.
!minelo
!maxelo
!minlevel
!maxlevel
!minrank
!maxrank
The battle waiting list now functions slightly different. Instead of counting the join time, the priority is now set by the time at which the player unspecced. So speccing will put you back at the end of the queue. There is a new command !maxevenplayers which can be used to enforce balanced teams. If the number of players at the start of the game is uneven and below the number set as !maxevenplayers, then the last person to unspec will be specced upon start.
For highly ranked players that want to play 1v1s outside the matchmaker, there is now the "Pro 1v1 Host". There, players of rank Neutron star and up can play 1v1 games which count for competitive (matchmaker) rating.
GoogleFrog has provided some new screenshots for the website backgrounds.