Media giants like Disney should have taken note back in 2010, when Blockbuster declared bankruptcy: Netflix was a budding serial killer in the making - and its victims of choice were giant corporate incumbents.

Back then, Blockbuster was in the business of renting DVDs. It started 2010 with 6,500 stores, but by July its stock had been delisted from the NYSE. By late September, Blockbuster had filed for bankruptcy-court protection. The rest is history, of course, but Disney, Comcast, News Corp. and others didn't see that past history as prologue until Netflix had already become a growing threat.

2010 also marked an important turning point for Netflix: It was the first year when the company had more subscribers streaming video than renting DVDs by mail. "Our core strategy is to grow our streaming subscription business," the company said in its 2010 annual report. "Going forward, we expect we will be primarily a global streaming business..."