Simsi - 10:03 pm on Dec 5, 2012 (gmt 0)
There is a User Ratings service in one of the niches I follow that provides a rating service. The concept is that multiple sites implement the rating code and thus ratings build up more quickly. The trade-off is a participating site can access the data.
At least one of the sites using the data displays the aggregate ratings in a rich snippet and it does, in my opinion, make the site look more authorative. Were a second site, third site etc to do the same, does anyone know if there is any impact on Google displaying the rich snippets - or even on ranking bearing in mind it could potentially be viewed as dupe content?