Batman: Arkham Asylum and Ghostbusters are both great games but not exclusives to PS3 or any better on PS3.
The rest of the suggestions are also great games too. Video gaming has improved by leaps and bounds. You will find there is something for everyone.
Wikipedia has a list of all PS3 games, with the exclusives noted:
http://en.wikipedia.org/wiki/PS3_exclusives
Also really liked InFamous as a great PS3 exclusive.