As I mentioned over here, I've also had it serve as a sort of neutral ground in my campaign, particularly since I decided that the giant hexagon wards against divinations - so it's a good place for plotters.
Yep, I did that too - did we just make it up, or is it official somewhere? :)
Factions - on their first visit my PCs got in with the Duskwardens and helped them deal with a Gray Render in the prison levels, then took out a renegade Zon-Kuthonite dark naga in the Undercity that had been using cloakers etc to raid the Dusklight Path. This time they're meeting the Pharasma clerics at the Godsmouth Ossuary getting a PC raised, and one has been invited to dinner with the Freemen - he has a rep as a 'people's champion' back in Korvosa.