Happy face most of the time :D
It has always been 15th. Everyone were just invited to play Halo 2 on 14th in case that Halo 2 would have been shutted down so early on 15th. It seems that they didn't do it early... so let's play some Halo 2 because this really should be the last day.
[Edited on 04.15.2010 6:23 AM PDT]