At these stores, you will find a very good selection of fiction and non-fiction, magazines, music (CDs) and even software. They are places to socialize, with cafes, couches to read on, concerts, readings and book signings. They're a great way to spend a rainy afternoon or even a night out, as most are open late.
CitiTip: Many of the mega bookstores have an "annex" with greatly reduced prices on books.