Although we don't believe in timing the market or panicking over daily movements, we do like to keep an eye on market changes -- just in case they're material to our investing thesis.

Investors must still be getting their bearings after the long holiday weekend: Stocks opened little changed this morning, with the S&P 500 and the narrower, price-weighted Dow Jones Industrial Average (DJINDICES:^DJI) down 0.10% and 0.26%, respectively, at 10:10 a.m. EST.

Over the past couple of weeks, I've highlighted the fact that retailers were planning for one of the most cutthroat Thanksgiving weekends in recent years. Dow component Wal-Mart Stores (NYSE:WMT), for example, began matching select Black Friday offers from Best Buy, Target and Toys "R" Us -- one week early. However, the numbers are coming in, and despite all the promotions, offers, and early opening hours, it now appears that retailers were unable to coax a higher aggregate spend out of shoppers. Still, one crafty competitor, Amazon.com (NASDAQ:AMZN), pulled off a massive publicity coup over the weekend (more on this later).

The National Retail Federation, the industry's principal trade group, now estimates that total spending over the Thanksgiving weekend fell 2.7% compared to last year, to $57.4 billion (note that, in inflation-adjusted terms, the drop is closer to 4%). Retailers did manage to pull in more shoppers, to the tune of 141 million (up 1.4%), but that did not compensate for a 4% decline in average spend to $404 from $427. That suggests that factors such as Obamacare and another potential budget standoff may be weighing on consumers.

Online shopping remains a growth area, particularly since many bricks-and-mortar retailers were offering the same deals online as in-store. Tablets are also fueling this growth, as the format is more convenient for browsing and shopping than smartphones; according to IBM, tablets accounted for 16.5% of purchases on Thanksgiving day against just 9% for smartphones. Online sales accounted for 44% of the weekend total, up from 41% last year and less than a quarter in 2006.

Thanksgiving weekend may be in the books, but the retail wars are far from over -- this is Cyber Monday, after all. Amazon.com has set itself up nicely on that front, with a huge publicity coup that was carefully orchestrated over the weekend. Appearing on 60 Minutes yesterday evening, Amazon CEO Jeff Bezos announced that the e-commerce juggernaut is developing unmanned aerial drones to deliver packages. While he dampened expectations by putting a four- to five-year timeframe on the program -- christened Prime Air -- he went on to say that "we'll be ready to enter commercial operations as soon as the necessary [FAA] rules are in place."

Given the amount of buzz the announcement is generating this morning, it could give a lift to Amazon's sales today -- even if the drones remain grounded for some time yet.

Fool contributor Alex Dumortier, CFA has no position in any stocks mentioned. The Motley Fool recommends Amazon.com. The Motley Fool owns shares of Amazon.com. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.