The Toonami crew has revealed that April 27th will be the debut of TOM 5, the new Absolution and the new on-air look for Toonami.
They also made this little announcement:
They managed to find a way to bring back IGPX, and it will begin airing that same night! They had mentioned previously that IGPX had been written off by Cartoon Network which would prevent them from being about to air it again. However (I'm guessing because CN and Toonami actually created the show) they managed get the rights back.
The plan seems to be to remove one of the Cowboy Bebop episodes to make room for IGPX. And it seems that this is NOT the replacement for Tenchi Muyo! GXP either, so something else may be coming too, in addition to One Piece.