MySpace is over, it's just not cool anymore.” So say the teens Lynn Hirschberg talked to for her recent article “The Music Man” in the New York Times Magazine. Grown-ups like Lee Lorenzen, a venture capitalist who has invested in Facebook-affiliated companies, agree: “MySpace is not based on authentic identities,” he told the NYT. So what's cool now? For the moment, it's Facebook, the social networking site founded by a Harvard student in 2004 that's “based on who you really are and who your friends really are,” as Lorenzen says. “That is who marketers really want to reach, not the 'fantasy you' that lives on MySpace and uses a photo of a model.”

Brands including Blockbuster, Conde Nast and Coca-Cola are all clamoring for the attention of Facebook's 60 million members, 40% of whom are over the age of 25. Is there room for book publishers and booksellers, too? The number of book-related tools on Facebook suggests so; out of the 5,000+ “applications” that exist on Facebook, some 125 of them are books-related. This week-in-the-life diary reveals what these applications are, how to use them—and why publishers and booksellers should care.

Monday

Number of books read about: 181

Number of people contacted about books: 3

Number of virtual gifts received: 1

10:19 a.m.

I log in to my Facebook profile page. It displays my photo and the “networks” I belong to (New York City, Reed Business and New York University). A “minifeed” lists new friends I've added, photos I've uploaded, virtual gifts I've received (one friend virtually “threw” Barack Obama at me) and applications I've added.

It's these applications—in English, features—that make Facebook so addictive. Mainly created by techies who aren't officially linked to Facebook, applications enhance a user's profile. Last May, Facebook invited software developers to create applications for the site to try to profit from them (by placing ads alongside the applications); there are now more than 5,000 on the site. Among the most popular ones are Where I've Been, which lets users pinpoint places they've visited on a map; and Scrabulous, which facilitates online Scrabble games between friends. Considering variables like the number of users, frequency of use and advertising revenue, investor Lorenzen values popular Facebook applications at around $2 million each.

This morning, there's an invitation: “Your friend Elyssa would like to share Visual Bookshelf with you.” I follow the simple instructions, and within seconds I've successfully added Visual Bookshelf to my profile. Ten of my Facebook friends use this application.

But my Visual Bookshelf is empty. I search Amazon, find Peter Hessler's Oracle Bones and add it to my “currently reading” list. What's next? “Add your $0.02,” “spread/recommend” the book to friends or buy similar books at Amazon. This last option doesn't work so well, though: there's a list of books that are related to Oracle Bones only in title, not subject, such as The Oracle of the Bones, a book about bonecasting—not China. Strike one against VB. Its efforts to get me to buy books similar to the ones I'm reading have failed.

3:50 p.m.

I invited two friends to add Visual Bookshelf, and one has taken me up on the offer. But she and I both already have GoodReads accounts, so I already know everything she's read recently, making VB redundant. One thing I can do on VB that I can't do on GoodReads is comment on a friend's book taste. This seems a little snooty, so in that spirit I comment on Anne's bookshelf: “You have impeccable taste, dahling.”

Tuesday

Number of books read about: 98

Number of books purchased: 1

Number of virtual gifts given (“chucked,” actually): 2

Number of people contacted about books: 3

9:33 a.m.

I see Anne added The Glass Castle to her bookshelf. Turns out 5,653 other Facebook users have placed this book on their Visual Bookshelf, too. Anne—and 6,037 other people—also added Eat, Pray, Love to their shelves. This information is useless to me, as both these books are already huge bestsellers. But one update does enlighten: my friend Jenny is currently reading Tolstoy Lied: A Love Story. I haven't heard of this book, so I click through and read about it. Score one for VB: it has successfully introduced me to a new book. I click the Amazon link and place my order.

2:54 p.m.

A little bored with Visual Bookshelf, I check out another application, Books iRead. It seems similar to VB. I add the application, then add a book to my “reads,” and it's easy to rate it from one to five stars. iRead invites me to “chuck” a book at a friend, explaining, “Want to recommend a book to someone? At wit's end with someone? Want to give them a reality check? Maybe you want to say 'I'm sorry'? Or just send them a sweet note. Now you can say it with a book—chuck a book!” I chuck Charlotte's Web at Anne and The Secret at Rachel.

iRead seems more playful than VB, and not just because it lets you throw books at people. You can add books under categories like “wanna read” and “heck no.” I also like iRead because it's easy to see how your friends rated books.

Wednesday

Number of books read about: 71

Number of people contacted about books: 5

Number of requests for friendship received from random people: 1

Number of people I stalked: 1

10:50 a.m.

It's a slow morning: my friend Darren added Visual Bookshelf; he's currently reading The Wind-Up Bird Chronicles; Marc read Songs of Innocence by Richard Aleas.

There's a friend request from someone named Psychic Poet. He is a male born in 1979; hometown: “Israel.” His profile description reads, “Searching for... A Successful Publisher for my Poetry Book inspired by A Legend Named Juli@.” I think I'll pass.

3:45 p.m

The novelty of both iReads and Visual Bookshelf have worn off (or do I have an extremely short attention span?), so I return to what I know: GoodReads. This application is actually tied to a full-fledged social networking site of its own, where I already have an account—and 133 books logged in it. I add The Fortune Cookie Chronicles to my “currently reading” shelf on GoodReads. The system tells me one other person has added this book to their “currently reading” shelf: Yvonne, a 26-year-old in Clackamas, Ore. I check out Yvonne's profile. Her favorite books: “The Great Gatsby, The Da Vinci Code, The Notebook (along with most anything by Nicholas Sparks), Barbie Loves L.A., the Bible, Shopgirl.”

I leave GoodReads, go to iRead and look up The Fortune Cookie Chronicles, and there's Yvonne again, as well as Catherine, of Tampa Bay, Fla. I decide to make my first contact with a total stranger on Facebook, writing on her wall (the equivalent of an inbox that all your friends can see), “Hi! I see you have The Fortune Cookie Chronicles on your bookshelf—just wondering how you're liking it so far.” Gulp. I feel like a stalker.

Thursday

Number of books read about: 239

Number of people contacted about books: 0

11:06 a.m.

Bookshelf applications are the most popular books-related tools on Facebook. Besides Visual Bookshelf, GoodReads and Books iRead, there are many others, including My Books, aNobii Books and, simply, Books. Plus Shelfari and LibraryThing, which also exist on their own, outside Facebook. With only small differences separating these applications, most seem redundant, and it looks like only a few have gained real traction on the site.

There are also a hodgepodge of book- and author-specific applications. The For Dummies Books application lets you create your own book jacket with the familiar yellow-and-black “For Dummies” look and then post it on your profile page (e.g., “Do It Yourself Colorectal Exams”). Another application, Rick Warren Quotes Bible, delivers daily quotes from Warren's books to your Facebook profile. There's even an application spun from the works of two DK authors who have written books on reflexology. These applications weren't created by the publishers; rather, they were developed by authors and fans.

Friday

Number of books I have catalogued on my Facebook profile page: 141

Number of friends with whom I've talked books this week: 25

Number of responses from people I've stalked: 0

3:45 p.m.

With the week ending, I take inventory of who's reading what. Books iRead informs me that Kerri's reading The Septembers of Shiraz, and that Marc gave one star to Will Storr vs. the Supernatural. On Visual Bookshelf, I see Kate's got a thing for books by Bret Easton Ellis and Jay McInerney, having added seven of them within two days. Elyssa has already added 71 books to her page, including Veronica by Mary Gaitskill. I glance around my desk and notice the galley for Last Last Chance, a debut novel from FSG. On a whim, I search Facebook for its author, Fiona Maazel. I find her, and see she's just added The Road by Cormac McCarthy to her Visual Bookshelf.

My stalking and snooping complete, I throw in the Facebook towel for the week.