In the latest salvo in the ongoing tablet/e-reader wars, Amazon announced an upgraded suite of tablet devices that will include the new Kindle Fire HDX, an upgraded version of the Kindle HD tablet that offers an even higher resolution screen in two sizes (7-inch for $229 16GB; 8.9-inch for $379 16GB) and a new version of the 7-inch Kindle HD for $139 (8GB). All the new Kindle Fire tablets offer upgraded hardware, a new version of the Fire OS, and better battery life, in addition to aggressively competitive prices.

The new tablet devices are significantly lighter, offer front and rear cameras on the HDX models (no camera on $139 Kindle HD), better battery life (17 hours for reading), more powerful 2.2 GHZ quad-core processors in the HDX models, super high resolution screens (2560x1600 vs the previous 1920x1200) for the HDX devices and a “second screen” feature that lets HDX devices users “throw” the image on their tablets onto a larger TV screen. There’s even a new “Mayday” button on the upgraded devices that summons instant (15 seconds or less Amazon claims) free 24/7 tech support in addition to the devices having upgraded web browsing, email and other features.

Amazon is also offering a new Origami cover, a cleverly designed cover that folds into a stand for the Kindle tablets. Amazon is also offering a variety of e-book loaning and video services tied to Amazon Prime and the retailer will continue to offer the older 8.9-inch Kindle HD at the reduced price of $269.

The book market seems to have sparked a tablet development war. This new suite of upgraded Kindle tablets comes about month after Kobo released its own set of upgraded, competitively priced tablets and the new Amazon devices seemed to have been priced with Kobo’s newly released Arc tablets in mind. And there’s likely more new device releases to come. By all accounts B&N plans to release a new Nook e-reading device, tablet or e-reader, this fall. It’s a buyers market in tablets these days with the digital reading marketplace awash in high performance tablets and dedicated e-readers offered for shockingly reasonable prices.

“It’s been just two years since we introduced the first Kindle Fire, and the team is innovating at an unbelievable speed,” said Jeff Bezos, Amazon.com Founder and CEO. “We’ve worked hard to pack this much hardware, innovation, and customer obsession into these prices.”