As Americans finished Thanksgiving dinner with family and friends, the Organization for Petroleum Exporting Countries (OPEC for short) hosted a small gathering of their own. The agenda was brief. The consequences were significant, though likely not entirely understood.

Pre-meeting data exposed the reality of both excess supply and softness in demand for the commodity known as black gold. Knowing full well that simply maintaining production would trigger a decline in price, the Saudi-led committee voted to hold production steady.

The resulting sell-off has been violent and unrelenting. A sale that began in earnest on Black Friday shows no indication of abating, taking prices per barrel from $73.70 to $54.18 in 21 days.

Toyota Tundra and Ford Super Duty owners are have reason to be particularly thankful. Fuel prices under $2/gallon mean they can now fill their 35-gallon tanks for less than a Benjamin. The savings at the pump appear to be translating into immediate spending elsewhere. Low-end retailers in particular may find this month to be the merriest Christmas in recent memory.

While there is no mistaking that lower oil prices are translating into a large unexpected present under the tree of the American consumer this season, even a cursory analysis identifies some obvious losers and a host of growing uncertainties.

Wal-Mart’s gain is clearly Venezuela’s pain. For a country whose economy is entirely dependent on oil plunging prices has brought economic instability and political unrest. In the midst of the turmoil Venezuela has gotten particularly chummy with China. It’ll be interesting to see how the world’s largest creditor nation “partners” with the former Spanish colony now teetering on bankruptcy because its precious commodity is out of favor.

As if Russia needed more trouble, oil’s slide has abetted the plummeting of the ruble. Russia even had to lower Vodka prices to keep people happy (or at least sedated) this holiday season. Tensions are high in Nigeria, Libya and other African nations as well.

Saudia Arabia essentially sent roughnecks in North Dakota and West Texas a big lump of coal this Christmas. The royal family can extract black gold for a fraction of the cost incurred by domestic shale producers. The couchsurfing market in Midland, Texas has already hit the skids, a likely harbinger to billions in reduced capital expenditures in the year ahead.

While most expect oil prices to eventually recover, investors are wise to keep an eye on prices in 2015 lest these black gold dominos knock something else over in the meantime.