Kindle Fire ships over 3M units, may already be no. 2 tablet after iPad

Amazon’s ultra-cheap Kindle Fire has already shipped between 3 and 4 million units. Combined with news of excellent Black Friday sales last week, the Fire may already be the number two tablet after the Apple iPad.

As far back as August, analysts have predicted that a less expensive, Amazon-made alternative to the iPad could sell up to 5 million units before the end of the year. Amazon appears to be making those predictions a reality with its Kindle Fire, which retails at $199 and can be used to read e-books, browse the web, play casual games and download content like movies and TV shows. If it sells more than 5 million units, the Fire would be the best-selling Android-based tablet in the world, beating high-profile tablets from Samsung and Motorola.

The 3-to-4 million Kindle Fire unit shipping estimate comes courtesy of Digitimes. Citing unnamed sources, the report says Quanta — Amazon’s manufacturer — has already shipped up to 4 million units and will likely have 5 million shipped before the end of 2011.

The Kindle Fire launched Nov. 15 and features a 7-inch screen with 1024 x 600 resolution, a TI OMAP4 dual-core processor and 8GB of on-board storage. The tablet offers applications from Netflix, Facebook, Rovio, Electronic Arts, PopCap and more, which likely fueled adoption.

The Kindle Fire’s two largest competitors are the iPad, which retails for a minimum $499, and the Barnes & Noble Nook Tablet, which runs for $249. The iPad does a whole lot more than the Kindle Fire, but because it costs at least $300 more, penny-pinching consumers may decide they can do without those extra features. The Nook Tablet offers better base specs and performance than the Kindle Fire, but it lacks a content ecosystem of movies, TV shows and music to download.