As a company selling subscriptions another merge would be a very bad idea, so don't expect it any time soon imo.

They will want to have as much capacity for "new/returning" players as possible. I understand to us this sounds silly
but lets say they merge..every server is 2-3k peek time aside from the obvious problems with events etc what will they do
with all the "new/returning" people they have to expect when the next expansion hits? a new server? no.

I think when they give up with the game we will see a merge, but I hope that's no time soon as it will
likely spell the end of updates or any chance of another exp pack.

Careful what you wish for.