Extremely repetitive gameplay, the spirit form wasn't utilized as a game mechanic nearly as well as I'd hoped it would be, I finished the game on its normal difficulty setting in 3 hours, extremely shallow and poorly 'developed' story, if you could even say it was developed in any way and the gameplay overall simply didn't leave a lasting impact.
It may be worth noting I never played it multiplayer since I didn't have ADSL at the time, but to my understanding by the time it hit bargain bins, nobody was playing it multiplayer anymore anyway...
One thing that it does have to its credit is that it looked good and ran well at the time, though.