To be honest, I was playing it obsessively the first few days because of the nostalgia factor. FF8 is one of my all time favorite games, so Triple Triad brought back many fond memories. But now that I've beaten all the FF8 levels and collected all the cards, my nostalgia cravings have been sated, and my motivation to play has pretty much disappeared.
This is also why I've not really played the WoW version, they don't give me the same nostalgia fix.