Amazon.com, Inc. may be doing better with its new Kindle Fire tablet than many think. It's been no secret that the Kindle Fire, Amazon's first tablet, is already a big success after launching last month.

Most analysts have predicted that Amazon (NASDAQ: AMZN) will sell at least four million Kindle Fire tablets by the end of the year, despite some customer complaints over glitches, like a clumsy touchscreen and difficulty connecting to Wi-Fi. But Goldman Sachs expects Amazon to sell six million Kindle Fire tablets by the end of the year -- 50 percent more than some estimates.

Goldman Sachs also predicts in a research note that Amazon will sell between 15.5 and 20.5 million Kindle Fire tablets in 2012, the product's first full year of availability and despite a likely release of Apple's newest tablet expected in 2012, the iPad 3.

With the ability to consume all forms of media, at a price of $199, Amazon's Kindle Fire has provided a legitimate tablet device to a crowd that is more price conscious versus the significantly more expensive iPad or couldn't justify the spend as they already owned a laptop and a smartphone, Goldman Sachs analyst Heather Bellini wrote in a note. Further, the price point, in our belief, is below the threshold to be thought of as a major purchase and is suitable for gifts.

Amazon stock was trading Tuesday afternoon down 3.7 percent, or $7.02, to $182.50 on the NASDAQ.