Its charm lies in the fact that it is a pretty unique game concept that it executed with a certain amount of flair.
The graphics are clean and sharp, with plenty of colour. Four things though spring to mind as a negative:
1. You hear the same things being said over and over again by NPCs which becomes monotonous, and sometimes you just feel like letting your minions loose on them,
2. The variety of NPCs is greatly lacking,
3. Lack of a map (if there is one I haven't found it yet) makes exploring a bit of a headache.
4. The replayabilty is not great, but it is there if you enjoyed it the first time round.
Another point to bring out is that while your intentions are to be evil, your enemies are fifty times more evil, so you feel more like a hero than an antihero, or evil villain.
RPG elements are there, i.e. upgrading armour and weapons, but it is not as pronounced as you might want.
In a nutshell, it is a fun game that I would recommend to anybody who feels like playing something a bit fresh.