I haven't been to Nice, yet, but I'm going in June. While there are a number of things to see in Nice, it's best selling point is probably as a jumping off point to the restof the Riviera. Good bus and train connections to just about everything you want to see, plus some sites worth seeing in town. Cannes has little going for it but the beach, St. Tropez has poor transportation connections to the rest of the Riviera, Monaco is too expensive, and the hill towns (St. Paul de Vence, Eze, etc.,) aren't as convenient for seeing other sites by public transportation (and you don't really want to drive into Nice, Monaco, etc.).