I assume Fluther’s official days start on West coast U. S. time since the Fluther Gods both live in California, i.e., a day starts at 12 midnight Pacific time.
Every night at 12 midnight pacific time (0800 UT when no daylight savings time) I score one lurve point for consecutive days on Fluther. It doesn’t change with region. I’ve been in both Eastern time and Hawaiian time on Fluther and it doesn’t follow you.
New Fluther day always begins at 12 Midnight PST or PDT, depending on time of year.
I think the servers are located in St. Louis, MO. I think Slicehost uses http://www.datotel.com/ I ran a bunch of traceroutes and they all ended up in St. Louis. But that doesn’t really mean anything. You can set the time to whatever you want with co-location. It gives me a +1 at midnight PST so I assume they have it set for that since they both live here too.
Concurring with @AstroChuck and @johnpowell and @jonsblond, I get my point for consecutive days at 3am, and I’m in New York. So Fluther runs on Pacific time. (Worst. Time zone. Ever.)