In the United States, it is commonly used by Spanish-speakers and French-speakers, in addition to Italian-speakers.
When "ciao" is used by Americans, instead of looking sophisticated, they look like retards. So, if you're American.... just don't say it.
French: Alors, Maman. Je me vais. Ciao!
(OK, Mom. I'm leaving. Bye)
An American saying Ciao: Ciao, darling. I'm a prick because i say 'Ciao' to sound sophisticated
Ciao bello - goodbye boyfriend
David: C.I.A.O that memo, Kevin. Now we have run out of shirts since no one bothered to tell us to get extras.