Profile recommendations - what is it?

We plan to broadcast user recommendations on the following categories of sites: blogs, media, social networks.

What is it for?
First, to collect statistics. Secondly, we are interested in building a certain rating of user preferences. Probably, it will be interesting for many to find out which blogs and mass media are most often read by users of this site, which networks they are in, and so on.

We plan to ask for recommendations on the three categories of sites (blogs, media, social networks), but the list can be expanded, offer :-)