I blame the Hollywood screenwriters' strike.

At least that's how I'm justifying the gobs of time I find myself spending trolling for monster deals in the virtual aisles of Amazon.com (NASDAQ:AMZN) in recent days. I'm bored. There are bargains to be had. I may as well use the strike as a scapegoat.

After religiously scouring Amazon's best-seller lists during the telltale holiday shopping season, I have also learned a lot about where the hot gifts are and how Amazon is orchestrating its perpetually fluctuating sale prices.

Let me save you some time by pouring out the many lessons that Amazon.com has taught me as an investor.

1. Apple is going to make a killing
Everyone figures that the new iPods will be brisk sellers. Despite the carrier-exclusive deal, iPhones should be a hot cell-phone product. However, do you realize that Apple (NASDAQ:AAPL) is selling a ton of its flagship computing products, too?

As of this morning, six of the nine top-selling products at Amazon are MacBook and iMac systems. Only a steeply discounted Nokia (NYSE:NOK) tablet PC and a pair of marked-down Hewlett-Packard (NYSE:HPQ) laptops are crashing the party. And the dominance doesn't end there -- head out to Amazon's software store, and many of the hottest titles are for the Apple platform.

Will it be fair to classify Apple as a mere niche player in personal computing by the time the holiday dollars have been accounted for? Those "I'm a Mac, I'm a PC" ads appear to be resonating with consumers. What's Apple's market share heading into this quarter -- 6% or so? It doesn't take much of a gain to move the needle at that level, and anecdotal evidence points to the needle giving the Richter scale a run for its money this season.

2. Barbie deserves your pity
After Mattel (NYSE:MAT) signed up nearly 3 million users to its BarbieGirls.com virtual community, I felt sure that Barbie was back. Even Mattel's stigma over the embarrassing wave of recalls couldn't get in the way of this viral hotshot.

The clincher at the time was this: The community was free, but Barbie was rolling out $80 Barbie dolls that doubled as digital music players. The stylish players would also unlock certain areas and accessories within the BarbieGirls community.

Slam-dunk? Not exactly. Over the past week, Amazon has been marking them down to less than $20. Small discounts are fine, but when you're chopping 75% off the list price, it starts to feel more like a clearance sale.

3. Amazon is sneaky
Pulling the trigger on a purchase at Amazon is tricky because the prices can fluctuate wildly. However, one tactic in particular means either sheer genius on the part of Amazon or sheer frustration on the part of a potential buyer.

Amazon appears to be orchestrating demand by offering steep discounts on products, then occasionally raising them once the items climb the bestseller list. Obviously, Amazon has every right to do that, even if it's an illusion. I'll tell you where it gets dicey, though: Let's say Amazon is stocking the same item in three different colors. The list price is the same for each, but the prices for the individual colors are all over the map.

I'll even give you a specific example. A few days ago, the Sanyo Xacti HD700 camcorder was fetching $520 for silver, $380 for red, and $350 for brown. The brown model crept higher on the bestseller list; it is now priced at $500, with the silver version marked down to $400. Consumers who may not know any better may wind up grabbing the priciest model without realizing the strings that were pulled along the way. It's a shrewd strategy at Amazon, but it's also one that could backfire if consumers grow weary of the practice.

4. Online video rocks on Amazon
I'm not sure when Amazon began offering video clips on select items to go with the snapshots. The first one I ever saw was back in June, when Amazon teamed up with Starbucks' (NASDAQ:SBUX) Hear Music to promote Paul McCartney's new CD.  

There are a ton of clips now, especially in the toy store. That is perfect, giving parents the ability to check out toys and games in action to make sure they're appropriate and easy to assemble.

5. Amazon really wants the Kindle to rock
Even though it's been out of stock for weeks, with delivery dates pushed into 2008, Amazon continues to promote its e-book reader on its landing page. One can argue that all the buzz is simply pushing traffic to resellers such as eBay (NASDAQ:EBAY), where Kindles have been fetching as much as double their $399 retail price, but Amazon isn't going to mind the "hot gift" publicity.

Let's just hope its production can keep up with the demand it has created. The real gravy with the Kindle is in the digitally delivered books, magazines, and newspapers, and those need a large user base to truly take off.

So those are the five lessons. Now let's hope the Writers Guild of America can come to agreeable terms with the networks, so I can have a reason to pry myself away from an overloaded Amazon shopping cart.

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