We have our Destro guild on Volkmar now and our Order guild on Badlands. Those are the established guilds.
Some of us have rolled more Order chars on Iron Rock because of the high population and constant scenario pops. We are running a bunch of Tier1/Tier2/Tier3 groups on any given night. I have not even touched a quest on that server yet. Getting so much xp and renown xp just from the bazillion scenarios. Not really any longterm goals for that guild though. Just playing around in lower tiers on Iron Rock.
There are some 'issues' with the endgame right now and a lot of folks are rolling lowbies and having fun down in the lower tiers until they fix some of the issues with Tier4.
Come take a peek at the boards http://www.casualtiesguild.com/forums/index.php