Barnes & Noble has launched its latest salvo in it ongoing e-reader and tablet war with Amazon by releasing its new Nook HD+ and Nook HD tablets. The Nook HD+ is aimed at tackling the 8.9-inch Kindle Fire HD with a 9-inch display. The new Nook HD shares the same 7-inch screen dimensions as AmazonÃs 7-inch Kindle Fire HD. Both sets of devices from the two companys also share the same dual-core Texas Instruments OMAP 4470 processor.