Located in the Forum area of Caesar's, my wife and I love this restaurant. Trevi has everything you want in a restaurant. The menu (focused on southern Italian cuisine) is extensive. The food is served hot and is delicious. The wine list is very good as well. Prices are very reasonable, especially for a restaurant located in a major casino on The Strip.
Service is often an issue in the mid to low prices Vegas restaurants. However, we have dined at Trevi more than a dozen times over the past 15 years and we have never had poor service.
The atmosphere is great, with a faux Trevi Fountain as the central focus of the restaurant. People watching here is great too!