The nerf hasn't been implemented yet as far as I know. Erebus is still the same.
Also, the light side one the first tournament and from what I gather, they typically have the better players.
If you think the darkside players dropped out in the pantheon before the nerf even happened, then your nuts. People will see that despite the Erebus nerf, better players will beat lesser players. For instance, my slightly above average Erebus was lost 3 pantheon games yesterday thanks to people playing with friends some how ( two games the guys admitted they were partners).
Yeah, Forces of Light won the first match, but at that point in time Erebus was very unknown... it was Regulus that was cried over as being overpowered. Then once second Tournament came around, it was Unclean Beast and Erebus.... once players found out about Erebus being able to kill so quickly and effectively, they started using him... and if you watched the rankings at this point... the Darkness got a HUGE lead and all of the top players on the Darkness side were Erebus players.
And of course better players will beat weaker players... duh. What people are referring to when they speak of Erebus, is how, Erebus fighting in a 1vs1 against an opponent of the same skill level using any other Demigod, will always win. It's his batswarm/stun/bite/mist/bite/+minions/stun/mist/batswarm out/kill combo. Fast cooldowns, health, and extremely high DPS... all in a matter of seconds.... oh and invulnerability... oh.. and minions. It all combines for a character that pretty much can't be beat.