SLI and CrossFire are handled by the drivers, so you need to have a profile created by the vendor for your application. Else you are out of luck and people can only hack it (by renaming the exe to another game with support), but that's likely to be buggy.
That basically means that there won't be official SLI/CrossFire support until OT (or rather an OT game) becomes popular enough and it will be worth the effort for respective HW vendor.