Hmm I haven't noticed that yet (haven't been online today), but I played a 4v4 yesterday and the lag was all but unbearable. I assume Blizzard is changing something about 3v3 and 4v4 to prevent that massive amount of lag.
Thanks for the reply. I've been playing since day 1 and it was never playable for me. I've read somewhere that it was a UI problem and there was a fix to it but I've lost the page.