Online video may be wildly popular among the Internet savvy, but it is a minor part of the TV-viewing habits of the mainstream crowd. Because online video offerings are still catching on among the masses, the US Department of Justice is considering whether the proposed Comcast/NBC merger is really meant to lock up the market and keep the competition at bay, according to insiders speaking to the Wall Street Journal. If so, the companies could find themselves subject to certain guidelines from the DoJ or an antitrust suit, though the final ruling is still a ways away.

Comcast and NBC announced their plan to join forces late last year, sparking a DoJ investigation at the beginning of 2010. Since then, there has been plenty of debate over whether such a deal would hurt the online video industry—after all, Comcast is one of the biggest content distributors in the US, and NBC is one of the biggest content producers.

Comcast already owns a plethora of social networking- and online video-related ventures, and some critics expressed concern that Comcast might take over NBC's 32 percent stake in Hulu and subsequently cripple the service in favor of its own offerings. Additionally, companies that own content are required to offer shows to competitors at reasonable rates, but tight control over the online video market (and Comcast's already-in-motion plan to offer its own customers online access first) could affect how and when other TV providers get online access.

According to the WSJ's sources, the DoJ's investigations over the last eight months have been focused on such a possibility. "The concern is: Will Comcast's incumbent systems give them an incentive to slow down online distribution?" one unnamed person told the Journal.

Still, the same sources said that the department's investigations "aren't likely to kill the deal"—rather, they might result in certain restrictions on exclusive content, or guidelines for how Comcast must deal with NBC's rivals when it comes to licensing content.

Comcast has already promised that it won't pull a Tonya Harding on Hulu, and it seems likely that some sort of agreement will be made between the DoJ and Comcast before the merger is approved. If those options don't work out, the DoJ may eventually sue the two companies under the Sherman Antitrust Act, though that seems to be a last resort.