I had to search for iRead as it didn't appear in the side application area; it came up as weRead. Once I went in and clicked to add the application, a window opened asking me to invite my friends who didn't have the application. It seems the reason for this is so that weRead will become known to everyone on Facebook. I sent a request to a few of my friends whom I know love books. I quickly added a selection of books from the 'favorites' list and then was asked if I wanted to rate books, check out recommendations, etc.
It was fairly simple to add in books, though I was a bit overwhelmed by the sheer volume of choices for most of my selections. Even the sheer volume of things to do for each book felt overwhelming at first. However, once I spent a good amount of time on the site working with my books, it came far easier to me. I'm still not sure I like the actual look of the site, though. Nor do I like how many books they pull up with each search, still it's not horrid.
I would much rather prefer a drag and drop for adding books, but I'm not sure if there are any sites that have that particular aspect.