Just found this interesting site on the internet. Globo has radar/traffic cams in various parts of the city giving real time views of the traffic - no biggie there - but for those wanting to know a bit about what the city really looks like apart from the picture postcard views of the beaches at Ipa/Copa, Pao de Acucar, Corcovado/Christo Redentor and the Parque de Flamengo/ Baia de Botafogo, you might like it:
http://radar.g1.globo.com/rj/rio-de-janeiro