I tried several of these sites listed on the short list. Judy's Book was not what I expected. It was listed under city guides and reviews and what I found was discount coupons. I much preferred Yelp which was fun and took me where I wanted to go. I found that Yelp did what i expected it to do. I also tried Craig's List which was very easy to use.
I noticed that there were several sites that we had experience with such as Flickr, Rollyo and Library Thing.
I'm not sure what use Craig's List would be for the Library but it is good to know how to use these popular sites.