Update v1.1.1622:
Fix for the matchmaking server:

Matchmaking server update has been deployed to fix empty multiplayer lobby issue.

1.1 patch for the lagging issue

Patch v1.1.1622 has been released to address the severe lagging issue when not all the players could connect with every other player. Please note that the patch solves a number of cases, but there are still cases when the lagging will remain

Workaround for the lagging issue

By adjusting your latency through the F5 and F6 keys, you can minimize the stuttering you encounter while playing.
Adjust the latency just above the level the game runs smoothly, since to high latency levels will increase the input lag tremendous.
Keep in mind that this is just a workaround and will be fixed soon.