SPOILER:
The conclusion for this is simple, we've already seen Abbodon's imprisonment and eventual replacement with the God of Truth. Possibly the God of Truth, or Kormir-whatever floats your boat, will take a more active role in GW2 and we will see more of this sort of replacement. I could easily imagine a world where Menzies and Dhuum will gain much more power or overcome one or two of the current gods. Now, none of this can be assumed until GW:EN is out, i know. However the implications make me very giddy

Now, for the really far-out thinking...imagine a MONOTHIESTIC gw2. Doesn't sound too cool, i know, but thats also another plausibility. Perhaps the old gods were overthrown by Dhuum's and Menzies's combined effort and one of them turned on the other to take absolute control? I for one would love more involvment with godly affairs in gw and I hope they continue to implement that. In GW2 you will somewhere find a monument remembering the overthrow of abbadon and his servants and the rising of the God of Truth thanks to <imput char name>. A hundred years or two is a long time for things to happen in all of GW and we will have to catch up on that lore when the time comes XD