I can't speak for anyone else, but for me, it will be the game first and VoIP as a last resort. I do have a small group that will be joining me during Exposition, but in fact, I am looking forward to working with the players that choose and are born into my community; creating the story of our County together -in-game-.
From what Caspian has said in the past there will be in-character community recruitment tools set up on the forums after domain selection, and I fully intend on using those tools as opposed to trying to build now. My laws will be laws of my County, not regulations of guild conduct. Therefore if you break the laws, you will be treated accordingly. But I have no interest in dictating how folks should experience the game.
I could be wrong, but from what I know about the game it might not be feasible after launch for large guilds from other games to gather in CoE because of the mechanics right at character creation. Therefore, players might be setting themselves up for disappointment when expecting CoE to be like every other MMO out there.
There is no starting City and depending on your choices during creation your groups could end up spread out all over the continent.