I'm not sure who told you that it would be ready by April 13th but that was a lie.

They've never given a general time frame for the release of the game besides Spring 2008. Right now, it's at 95% and possibly in beta testing (they won't tell) which can last between a month and three months (maybe more), depending on how many glitches they find and fix and whether they decide to add something extra during the beta testing period. So it will be a while longer. When they get closer to the end of beta testing they will release a release date.