Effects on cats were discussed in a USDA risk assessment of a similar program in 2002 (http://www.aphis.usda.gov/wildlife_damage/nwrc/publications/...) -- basically, it looks like cats are likely to die if they eat the poisoned mice, but cats didn't seem interested in them.

Also, if I'm reading the report correctly, then (at least in the 2002 program), the baits were prepared by inserting (somehow) acetaminophen tablets into mouse carcasses. I think a cat that began to eat one of these mice would be likely not to swallow the pills (just based on the fact that I've never managed to get a cat to take a pill hidden in cat food).