The Digital Reader references a posting at Digital Inspiration (labnol.org) which claims that B&N only has about 25,500 e-books in its catalogue. The folks at Digital Inspiration came up with that number by running a Google search with the search terms
"buy this ebook" site=http://search.barnesandnoble.com
Nate the Great at The Digital Reader says that Digital Inspiration's numbers are wrong, that the correct number is about 29,000 e-books. Nate came up with that by running a Google search very similar to the above (just dropping the "http://"):
"buy this ebook" site=search.barnesandnoble.com
Nate defends this approach to determining catalogue size:
In this day and age, a professionally made site should be set up so Google can find every page. (If it’s not, then it’s the fault of the developers, not me.)
Nate then goes on to (erroneously) claim that of those 29,000 e-books, about 20,000 of them are from Smashwords because that's how many titles Smashwords has. Ergo, by his estimates, B&N only carries maybe 9000 e-book titles from major publishers.
I posted a rebuttal comment. If you do this B&N search, you'll see that the total size of B&N's e-book catalogue today is over 1,176,000, counting Google Books and all. If you do this popular B&N search, you'll see that the total number of free e-books on B&N is approximately 956,000 titles. Subtract the two and you get about 220,000 e-book titles that aren't free.
As for Smashwords, if you do this B&N search, you'll see that the total size of B&N's Smashwords catalog is about 9000 titles. And if you do this B&N search, you'll see that about 1000 of those are free. Contrary to Nate's assumptions, not all Smashwords titles are carried by the booksellers. The titles must qualify for Smashwords' Premium Catalog, and the author must select the booksellers that the title will be offered through (royalty rates vary).
Anyway, using those results we get about 212,000 e-book titles at B&N that aren't free and aren't from Smashwords. Which is slightly more than 29,000 or 25,500.
By the way, Nate also uses Google searches on a number of other e-book stores, showing catalogue sizes between 22K (Smashwords) and 128K (Kobo). But when he got to Amazon:
I left Amazon out of the mix. If you ran a similar search for them you’d get around 700k titles.That’s about the number they claim to have (even though most of the titles are in the public domain).
Similar nonsense was done in the Digital Inspiration article: removing public domain books from the reported catalogue size for all retailers except Amazon. If we're going to do that for Amazon, then we can go with the 1,176,000+ titles at B&N "(even though most of the titles are in the public domain)".