In yet another example of the online giant brazenly going after established players in new markets, Google this week launched its eBook store, called Google Books. The store takes on Amazon (whose Kindle bookstore dominates the market currently) and Apple (whose iBooks service is riding the popularity of the iPad).

"Today is the first page in a new chapter of our mission to improve access to the cultural and educational treasures we know as books," Google Books Product Manager Abraham Murray wrote in a blog post announcing the new service. "You can browse and search through the largest eBooks collection in the world with more than three million titles, including hundreds of thousands for sale."

Google's new eBook store offers books in the industry-standard ePub format, which works on PCs, Macs, all popular web browsers, most popular smartphones, the iPad, and virtually all eBook readers—with the Amazon Kindle being the most obvious and notable exception. Indeed, it seems odd that Amazon's best-selling device, which sits at the center of the dominant Kindle ecosystem, is being left out of this party, though Amazon could of course add ePub support at any time.

Content protection for Google Books is handled by Adobe's Content Server 4 software, Google says. This provides publishers with a way to securely publish their titles electronically in either ePub or PDF format.

As with the Kindle, there's no way for Google Books customers to share purchased titles. And like the Kindle, Google supports the ability to pick up where you left off in a book, no matter what device you use. So you might start reading on the web and then pick up in the same spot, automatically, when you access the same book on your phone.

Google's gotten a lot of publisher support for its new service, which suggests that these companies aren't particularly interested in handing Amazon a monopoly. Google cites more than 4,000 publishers as part of the US launch, including all the heavyweights, like McGraw-Hill, Penguin, Random House, Wiley, and so on. Additionally, independent booksellers will be able to augment their retail operations with online stores based on Google Books. Powells of Portland, Oregon, has already signed up, for example.

US-based access to Google Books is available today. Google promises international launches for the service in early 2011.

I'll be writing up a full report about the Google Books service soon on the SuperSite for Windows.