HardOCP received confirmation that Just Cause 2 is broken with ATI's Catalyst 10.5 drivers if you are using a Radeon HD 5970 in an Eyefinity configuration.
The handful of people that are affected by this issue are advised to downgrade to Catalyst 10.4 or wait until Catalyst 10.6 arrives sometime later this month.
AMD confirmed that Just Cause 2 is broken with the latest 10.5 drivers if you are using a Radeon HD 5970 and Eyefinity. Just when I was really starting to get into it too. The 5970 is about history though, two ASUS ROG Matrix 5870 Platinum cards will take its place. Guess it is back to 10.4 till 10.6 arrives or my Matrix cards, whichever comes first.