Just visited the site (March 2013). Unesco status or not it is certainly one of those places in Brazil that you just have to see anyway. Paraty is easly located between Rio (4 hours by bus) and Sao Paulo (6 hours by bus) with some frequent buses going both ways.
Historical nucleus of the town is almost intact. Its cobblestone streets and white mostly one-storey houses are just like in the towns of XVIII-XIX centuries. Currently a little bit touristic place with majority of houses changed into shops, pousadas still remained its own colonial old-fashioned character. Some streets especially during high tide resemble Venice thanks to flow of sea water into the town. Keep fingers crossed for Paraty's future inscription but who knows ...