I also own it, but I am very happy it is going to be on XBL.  This is my favorite game on the Saturn, and easily a top 5 game of all-time, it is an absolute classic.  I play all of the time still, and it will be awesome to get some on-line co-op going.
I hope they add the battle mode too, and that they still have the code to unlock all of the characters for use.  There is nothing better than a high level coughing old man vs. a low level dragon fight.
Finally, if they added anything to the game at all, a new stage or character or something...  I would likely make love to my 360.