Pros
People are typically friendly/helpful or at least not cutthroat. 401(k) is good. Louisville is a fairly nice city. Lots of opportunities to build out more robust processes (even if it is an uphill battle culturally and technologically at times).
Cons
Health benefits suck, and fitness centers are not free (ironic, right?). IT is behind the curve for Fortune 100 companies (no ERP, no wifi, blackberries instead of iPhones, excessive security, slow/inflexible process for IT projects, etc.). Company seems hesitant to get involved with the local community and charities (philanthropy is limited to grants through the Humana Foundation), in contrast to GE, Coca-Cola, and Expeditors, which aren't even based in Louisville but which nonetheless have a strong presence in the community.