According to media reports, Disney has said that it will no longer allow Netflix to advertise on most of its networks, including ABC and FX.  With Disney set to launch its own streaming service this fall, it said that it took the move due competitive concerns.  Since Netflix doesn't offer streaming sports, however, Disney said that it will still allow Netflix to advertise on ESPN.

While the major broadcast networks have historically not taken advertising that promotes competitors, non-advertiser supported subscription services like HBO and Netflix were not viewed as direct competitors.  Therefore, for the most part, the networks took their advertising.  

With the media wars continuing to heat up, and with more companies -- such as online retailers and wireless providers -- becoming content companies, the big question is whether this is a sign of things to come. What does this mean for advertisers and their agencies right now? At a minimum, they should consider whether they are promoting brands that may be seen as competitive in some way to the platforms on which they are planning to advertise.  If they are, they should make sure that those platforms will still accept their media buys.