The Kindle Fire HD has a slightly smaller display at 8.9 inches, but it keeps the pixel density up with a 1920-by-1200-pixel display, 254 ppi compared to the 264 ppi 2048-by-1536-pixel display on the iPad. It's also slightly thinner and lighter, making it easier to hold when reading or watching movies.

Perhaps most importantly, the Kindle Fire HD offers double the storage plus 4G connectivity at the same price as a Wi-Fi-only iPad.

The $499 Kindle Fire HD 8.9-inch 4G comes with 32GB of storage and a 4G radio, while the same money buys a third-generation Wi-Fi iPad with 16GB of storage. In comparison, a 32GB 4G iPad costs $729.

If you put 4G connectivity aside, the Kindle Fire HD becomes an even fiercer rival to the iPad. A 16GB Wi-Fi-only 8.9-inch Fire HD costs $200 less than the comparable iPad, and even $100 less than the $399 iPad 2 Apple is selling (which costs $529 with 3G support).

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