The 1.5 pre-release is now available, which means that the full release will probably be next week. Please remember that the server cannot upgrade until Bukkit upgrades to the new version, and there's typically a few days lag time after the full release before that happens. So, don't update until I make a post saying you can, unless you don't mind being unable to connect to the server.

Of course, the 1.5 update is coming out at the same time as Heart of the Swarm, which is an entirely separate issue...