Neighbors friendly outdoor cat gave me a playful bite that very lightly scratched my skin. less than half an inch in length. im in southern usa and up to date on tetanus. should i worry about rabies?

The cat should be immunized against rabies as required by law. ( your neighbors may be able to confirm by checking with the local vet). Usually in such cases the animal is quarantined for 10 days, if no signs of disease, rabies is ruled out. Check cdc.gov for rabies transmission. Other common infections remain possible and wound should be watched closely until healed.