In the past there was a yearly Developer Meeting. That meeting would take place at PgCon. PgCon is held in May at the University of Ottawa, Canada. It is a small but great developer conference.
This year we are going to have two plus probably an informal one for a total of three. The first of which is taking place now @ FOSDEM. The current list of attendees to that meeting and the discussion points are listed there.
The informal one will likely happen at PgConf.US in April. As it is the largest North American PostgreSQL conference, it makes sense that a lot of the developers you will see on the list at the FOSSDEM developer meeting will also be at PgConf.US. Even better, we may see some of the "regrets" that were not able to make FOSSDEM. This allows for a great amount of catch-up.
The second formal meeting will happen at PgCon per the usual schedule.
These are invitation only meetings so don't plan to just show up. The way to get invited is to be a prolific developer/contributor to PostgreSQL.Org and we are always looking for more of those. Without them, we couldn't be the leading and most advanced database in the world!
I would be remiss if I didn't also mention that the CFP for PgConf.US 2016 is closing this coming Sunday. Get those presentations in!