In the last couple of days the online play in this game seems fixed. I used to not be able to join games, but now we play games, with no lag. I don't know if I've just gotten lucky or something, but it all seems to work now. 

I played a ranked 4-player arena match for the first time today, it was crazy.

I haven't tried playing today, but last night it froze on me 2 times and took approximately 30 minutes to successfully join and play a 4 player CC game :\

I've only played local so I wouldn't know, but I hope the online is fixed so I can play online when I want to.

"I played a ranked 4-player arena match for the first time today, it was crazy."

It's been about a week ago,but I tried to play some online and it would say I was connected to a 4 player game and then kick off.