Over the weekend the New York Times reported that Wal-Mart executives had threatened movie studios not to follow Disney's footsteps by selling movies through iTunes.

Sound familiar? It should. In October of 2004, Rolling Stone reported on Wal-Mart's efforts to strong-arm record labels into dropping their wholesale prices to a level that would enable a $10 retail price. All the majors "agreed to supply some popular albums to Wal-Mart's $9.72 program," according to the article. Not all, but some.

Since then, Universal Music Group announced its plan to offer CDs in a three-tier system. The cheapest of the three would be a no-frills CD in a sleeve (though according to the report this would be only for catalog titles). The plan was for the U.S. to see how it goes in Europe and Asia before adoping the new system.

Is Wal-Mart posturing? Probably. Going through on its promise of "serious ramificaitons" would mean it wouldn't stock popular titles that its customers expect the chain to carry. Committing to a full boycott would hurt customer experience. A harsh tone and a few threats may get Wal-Mart something: maybe price concessions, maybe exclusives, maybe higher wholesale prices at iTunes.

Bottom line: This is the kind of roadblock digital companies will run across from time to time. Physical retailers aren't going to quietly concede their market shares. Analysts and experts tend to forget about these things when forecasting the transition to digital from physical entertainment. They think studios and labels will be the only impediment.