When I kept a book blog, I used to work with them as a tour host. Giselle was always very professional, prompt in communication and did keep track of the bloggers to make sure that they posted. Post information was sent on time, with graphics provided, all links given, synopsises etc.
The only criticism I really have of them is that I don't always think they do the best job of matching books to blogs. I also think that there is a lot of variance in the quality of posts/reviews that come out between various blogs that they work with.