http://gamerscoreblog.com/team/archive/2008/01/18/UndertowFreeofCharge.aspx
Tried the trial version when it came out and deleted it straight away. Its garbage but Ill take it for the gamerpoints as its free.
They really should have given away whatever game they are releasing next though, as there are gonna be a lot of people who already have the game so theyll get nothing.
MajorNelson has already stated that if people already own the game, they can get in touch to work something else out.