Book Spot - Check this site out for weekly current bestsellers, an interesting FAQ section titled "You Asked For It", great links to reading lists including a large "First Chapters" section. This is a really extensive site covering everything from young adult paperback lists to books in the movies, literary award listings and poetry.
BookBrowse - An excellent reader's advisory site. Offers an extensive array of reading lists, from sequels and series titles to genre fiction and forthcoming titles. Choose book reviews, pseudonyms, author interviews or visit one of the countless reading related web links. Great place for readers to discover new authors and titles.
Bookreporter - This site is chock full of reviews and excerpts, contests, reader comments, surveys and polls. Includes "Best of" lists, current Book and Author news, Book Award lists and more.
Goodreads - Part book site, part social networking, this is an exciting combination. Highlights include Listopia (lots of booklists), keep track of your reading with your own book shelf and an e-mail and friends feature. Check out authors and librarians who have joined Goodreads and see what they are reading.