Barnes & Noble has high hopes for its new e-book reader, the NOOK Color. Described by some as half e-reader, half-tablet, the $250 device, which runs on Google’s Android operating system, has been sold an estimated 3m times since its debut last November.

Now, B&N is eager to develop a strong developer ecosystem. The retailer has launched a NOOK SDK 1.0 and a shiny new NOOK Developer website which invites developers to “change the future of reading” with B&N.

B&N is going all out to attract developers. The NOOK Developer website pitches NOOK development as a great opportunity. “Nobody knows more about readers than Barnes & Noble and there’s no better
time to capitalize on this market opportunity
,” B&N states on the website. “We are opening our doors to your innovation by offering unprecedented access to
unique merchandising opportunities.

The NOOK Color, of course, isn’t the iPad. Given that the NOOK Color is being marketed as an e-book reader, B&N is not surprisingly encouraging developers to focus their efforts on “reading-centric” applications. These might include dictionaries, how-to guides, studying tools, and educational games.

The million-dollar question, of course, is whether NOOK Color owners will open their wallets to buy such apps. B&N can court developers and welcome them with open arms, but at the end of the day, it’s all about the ability to sell. On this front, developing for the NOOK Color early on may require some amount of faith. According to a recent survey conducted by ChangeWave, the iPad accounts for nearly half of e-book purchases, and the iPad may be cannibalizing Kindle sales, raising questions about the NOOK Color’s long-term prospects. On the other hand, a poll taken by Piper Jaffray found that only 6% of iPad 2 buyers on iPad 2 launch day planned to use their iPads to read books. Given that NOOK Color owners ostensibly purchased a NOOK to buy e-books, it seems possible that developers building “reading-centric” apps will find a more receptive customer base with the NOOK Color.

Whatever the answer to these questions, the good news for developers is that the number of platforms on which to develop keeps growing, and judging from B&N’s NOOK Developer site, the retailer is serious about building a solid platform and working closely with developers to create great experiences for its customers. What’s not to like about that?