This thread again...
The choice on who got to keep what name was random, it was not based whether or not you had the name first.
It wasn't entirely random. I was a subscriber since launch, and got merged twice. I kept all 5 of the names I had, except for a level 1 alt I hadn't played at all. From what they've said, they considered length of play and other factors, and probably did favor active subscribers, since you don't want to risk offending someone who's still playing and might quit instead of someone who quit and might not come back.
OP, sorry dude. I wasn't in favor of the forced mergers, but they rolled out too many servers at launch. Nothing to be done about it now.