Rovinj is Super Cute. It is one of those post card picture-perfect places - built on a hill jutting out into the water [it used to be an island], crowned by a baroque church, surrounded by red tile roofs and a deep blue harbor teeming with boats. It is also filled with tourists, most of whom stay at the big resorts across the harbor. If you decide to stay in one of the bigger resorts in the area, skip the Eden and Lone and stay at the Monte Mulini. It's worth the few extra bucks.
Rovinj has one of the best restaurants in Croatia, based on our experience. You can read the review for Monte on Tripadvisor here. Rovinj is also a good base to explore nearby resort towns and the interior hill country.