Since Barnes & Noble released the Nook Color e-reader in October 2010, it has straddled the fine line between e-reader and tablet, with the bookseller even referring to it as a "reader's tablet." Then, earlier this year, techies were in a tizzy over a relatively simple hack that could transform the $249 gadget into a basic Android tablet. Now, Barnes & Noble has released a major update to the Nook Color which pushes it even further toward the tablet camp, no hacking needed. The update includes built-in email, support for Flash and the Android 2.2 operating system, and a small app store just for the Nook Color. Does this mean it's a tablet now, and not just a mere e-reader?

The LCD screen already made the Nook a tablet: Even before this update, the Nook Color fell into the tablet camp, says tech analyst Rob Enderle, as quoted by Tech News World. The difference is the screen. E-readers like the Kindle use a grey e-ink display, while tablets, including the Nook Color, use a brighter, color LCD screen. "The tradeoff is that e-paper is vastly better for reading, while the [high-resolution LCD display] is vastly better for video."
"Nook Color becomes dwarf star in tablet universe"

And these upgrades cement its tablet status: The "major update" to the Nook Color "pushes the device far into tablet territory," says Stan Schroeder at CNN. It now has built-in email that allows a user to check multiple webmail acccounts from one place, something the BlackBerry Playbook — a tablet that costs twice as much — doesn't have. The Nook is now a "solid bridge" between a basic e-reader like the Kindle and a souped-up tablet like the iPad.
"Nook Color update turns the e-reader into a tablet"

No, it's still really an e-reader: "At its core, the Nook Color is still an e-reading device," even though Barnes & Noble is clearly positioning the $249 gadget as a cheaper alternative to the iPad, says Peter Pachal at PCMag. The upgrade definitely enhances the e-reader experience, especially the addition of an app store just for Nook Color. But compared to other high-tech tablets, it's still "plainly inferior." There are only 125 Nook apps on offer, compared to the iPad's 65,000.
"With upgrade, Barnes & Noble positions Nook Color as cheap iPad alternative"