Just when the competition between Amazon's (AMZN) Kindle device and Apple's (AAPL) iPad tablet were starting to heat up, a third and powerful entrant may throw itself into the ring next month. Google (GOOG) is tapped to start selling digital books come June.

What devices will be able to read these digital books may be a mystery (for now), but you can bet that Google's Android operating system may be behind a new device sold in consumer electronics stores, and perhaps Google's website itself.

When Apple, Inc. (AAPL) introduced the iPad tablet computing device earlier this month, many saw it as immediately being the e-reader device to beat. After all, there were 60,000 e-books in Apple's iBooks store, right? Lest we forget that e-tailer extraordinaire Amazon.com, Inc. (AMZN) released its Kindle e-reader device in 2007 and has over 400,000 books available in the Kindle store for purchase and download. But, with the Apple brand behind it, everyone seems to have forgotten about the Kindle.

Dell's (DELL) is about to start thinking that it's newer Mini 5 hybrid device will be an Apple (AAPL) iPad competitor. Each device has not even been released yet, and there are competitive stirrings already afoot. The Dell unit, which looks like a large smartphone but not quite as large as a tablet computer, will bring a ton of Amazon (AMZN) services to bear in order to try and compete with the Apple content ecosystem that will surely blow all others away once the iPad starts shipping next month. Can an Amazon Kindle e-reader application pre-loaded on Dell's device really give an iPad a run for its money?

Taiwan's Acer became the world's second-largest PC maker in 2009 by getting very aggressive in retail with pricing and positioning its three brands across all pricing segments. The eMachines brand is entry-level, the Acer brand seems to be mid-level and Acer has positioned the Gateway brand as a premium product.

All told, Acer's might unseated Dell (DELL) and the company shows no signs of slowing down sales. It even was an early participant in the netbook category last year, helping it capture sales in that red-hot category as well.

A rally that began last year has already run up the prices of some stocks, creating small bubbles across the market. Some investors might be pushing prices higher ahead of their time for 62 of the stocks in the S&P 500 index. These companies now have P/E ratios of above 70, up from 23 a year ago. Says Robert Maltbie of Singular Research, "We have to temper some of this crazy bullishness." He tells USA Today that when P/E ratios approach 70, a stock can begin to have problems.

So, why are some prices being run up? As usual, any hope of rational price drivers is the domain of dreamers. Investors have found their favorites and sometimes haven't allowed reality to become a constraint on their excitement. Take a look at five reasons below:

Looking back on what became a tough end to a tough year for the retail sector, the one bright spot was the online sector. Shoppers whipped out their plastic at a record rate on Black Friday, a trend that continued throughout the season.

The Amazon (AMZN) Kindle killed the competition, reinforcing the status of the online channel as the future of the retail business. Social media, in particular, had its first real test this year, as many companies -- including Best Buy (BBY), JCPenney (JCP) and Target (TGT) -- used the likes of Twitter and Facebook to engage customers, publicize sales and generally increase revenue. The next stage in the evolution, of course, is to use shopping behavior to trigger viral results.

Retailers appear to have been rescued at the last minute, according to data from the International Council of Shopping Centers. Shoppers looking for deals the week before Christmas -- and making up for the day lost to stormy weather on the East Coast -- spent aggressively, sparing the retail sector a dismal 2008-like performance.

The healthy conclusion to the holiday season led to a positive change from November and made December one of only three months (including September and October) in which retail sales increased year-over-year.

For a company that hasn't even admitted to a new product, expectations are awfully high. The word is out that Apple (AAPL) will be unveiling a tablet computer at a major product launch this month.

Former Google (GOOG) exec Lee Kai-fu put out on his blog that he knows its coming, citing an anonymous source, and that the device would sell for less than $1,000. It's going to have a 10.1-inch screen and three-dimensional graphics, he continued, according to a Bloomberg News report, saying it would look like a large iPhone.

While much of the Midwestern United States was reeling from a record winter blizzard on Saturday, web e-tailer Amazon.com (AMZN) announced that the Kindle e-book reader (and much more) had become the most-gifted product in its history over the Christmas holiday. Although specific numbers were not available, Amazon.com also indicated that more electronic books for the kindle were sold than physical books -- another first.

Is Amazon's version of the transition from physical media to electronic media happening faster than it imagined? Maybe we can't go that far yet -- and the electronic restrictions will keep many away (including this writer), but Amazon clearly has a hit product here.

Five of the largest companies in the print business are testing the digital waters together. Rather than yield their content to alien formats, Time Inc. (TWX), News Corp. (NWS), Conde Nast, Hearst and Meredith Corp. have announced plans to develop a digital content format of their own. This new product would compete with the newly released Nook from Barnes & Noble (BKS), as well as one from Sony (SNE) and the industry-leading Kindle from Amazon (AMZN). The new e-reader content will come in color and in a format that would work across several devices.

The five media companies are equal partners in this joint venture, which will allow publishers to set their own prices for their content -- an obvious response to what they see as unfavorable revenue share deals offered by Amazon earlier this year. Rupert Murdoch has been particularly vocal on this issue, particularly about the fact that News Corp. only receives a little more than a third of the $14.99 a month it costs to subscribe to the Wall Street Journal on a Kindle. He says of the device that it's "a fantastic invention for reading books. It is not much of an experience for newspapers."

Black Friday's online sales were up 35% year over year, and early reports for Cyber Monday put the gain at 19.6%. Amazon (AMZN), as an online pure-play, has felt a lift from both these factors, but its execution in the e-reader category can't be ignored. While Sony (SNE) and Barnes & Noble (BKS) have already sold out of their respective devices, effectively taking them out of the game until early next year, Amazon's Kindle continues to fly off the shelves.

So, what's the prize for effective forecasting and a supply chain that can delivery on it? A new record!

Amazon had its best Kindle month yet in 2009, though it wouldn't reveal how many of the devices it has moved or the revenue it's pulled in from these sales. All it would say is that some buyers were buying more than one Kindle at a time, and businesses and organizations were picking them up in volume for employees or clients.

The next month is the one that matters most to the retail sector. It will dominate the conversation when Q4 and full-year financials are reported. A strong Black Friday brought with it concerns that momentum will fade, but opportunity is not dispensed equally. Some retailers will come through the season better than others, and industry experts have already chosen their favorites.

Michael Dart, senior partner at Kurt Salmon Associates, says, "We are seeing a paradigm shift in the way consumer interprets value and what they are looking for." The winners will do more than pitch deep discounts to convince consumers to part with their hard-earned cash.

Online retail sales are expected to increase 3% to $28.8 billion for this year's holiday season. The analysts at comScore include traditional retailers, like Macy's (M) in this estimate, but don't count auction sites like eBay (EBAY), travel or corporate sales. The estimate compares favorably against the National Retail Federation's forecast of a 1% year-over-year drop for all retail sales and exceeds the industry's most aggressive holiday season sales estimates of 2%.

Last year, online retail sales fell 3% for the holiday season, the first decline since the industry started keeping score in 2001. Even if we don't hit the 3% growth level this year, 2009 is still expected to be better than 2008, now that the economy has stabilized (at least relative to last year).