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Barnes & Noble launches new Nook HD

William Lynch, chief executive of Barnes & Noble, showed the new Nook HD+ (left) and the Nook HD.

Newscast via Bloomberg News

William Lynch, chief executive of Barnes & Noble, showed the new Nook HD+ (left) and the Nook HD.

NEW YORK — Barnes & Noble is rolling out two versions of its Nook tablet with sleek new hardware and a sharper high-definition screen. The bookseller’s move heightens the already intense tablet wars heading into the holiday season.

Barnes & Noble said Wednesday that its new Nook HD will come in two sizes, one with a 7-inch screen (measured diagonally), starting at $199, and one with a 9-inch screen, called Nook HD+ and starting at $269.

In addition to the new HD screen and a lighter body, Barnes & Noble is increasing the services the Nook offers, adding a video purchase and rental service, allowing users to maintain different profiles, and making it easier to browse book and magazine titles.

Barnes & Noble, the largest traditional US bookseller, has invested heavily in its Nook e-reader­ and e-books. In its most recent fiscal quarter, sales of digital content surged 46 percent, but revenue from devices dropped, partly due to lower prices. Nook prices in the May-July period were about 23 percent lower than a year earlier.

The company is seeking to offset tough competition from online retailers such as Amazon.com as consumers move away from traditional books and DVDs to electronic books and streaming video.

The Nook HD is an upgrade to the hardware and services offered by previous tablets, the Nook Tablet and Nook Color, which are being phased out. The company will continue to sell its smaller black-and-white e-reader, Nook Simple Touch, for $99, and a backlit Nook Simple Touch for $139. The Nook HD runs on Google’s Android 4.0 system and includes Barnes & Noble’s own app store and browser.

Tablets are again expected to be hot holiday items. The new Nooks come on the heels of ­Amazon.com’s announcement this month that it will offer four new varieties of its Kindle tablet, including a high-definition Kindle Fire with an 8.9-inch screen that starts at $299. That compares with Apple Inc.’s iPad with a 9.7-inch diagonal screen and $499 starting price.

The iPad is the most popular tablet, and that is not expected to change soon. Seven of every 10 tablets sold in the second quarter were iPads, according to IHS iSuppli. Amazon.com has a 4.2 percent share of the tablet market; Barnes & Noble has 1.9 percent.

Even so, the category is growing rapidly. An estimated 112.5 million Americans, one-third of adults, are expected to have tablets by 2016, according to Forrester Research.

The new Nook presents a tough choice for consumers seeking a cheaper alternative to the iPad, analysts say. The 7-inch Nook HD is slightly lighter and narrower, with a sharper display than the similarly priced 7-inch Kindle Fire.

‘‘If the decision the consumer is making is whether to buy based on hardware, these new Nooks will beat out Amazon,’’ said Forrester’s James McQuivey. ‘‘But that’s not the decision every consumer is going to make — hardware is only as good as the services the hardware enables.’’

So far, Amazon offers more services, McQuivey said, with a bigger app store, more extensive video library, vast product offerings, and the Amazon Prime free-shipping service.

In an attempt to measure up, Barnes & Noble is launching a video service this fall that lets users buy and watch movies and TV shows on mobile devices and televisions. Major studios, including HBO, Sony Pictures, Viacom, and Warner Brothers, will participate. Scrapbook and catalog browsing features have been added.

One wild card in Barnes & Noble’s favor: Walmart and Target, threatened by Amazon’s online retail operations, won’t carry the Kindle. The retailers will sell Nooks, as well as other tablets like the iPad.