Let me start with a Wikipedia quote for those (like me) who do not know about Sling TV.
Sling TV is an American over-the-top internet television service that is owned by the Sling TV LLC subsidiary of Dish Network. Unveiled on January 5, 2015, at the Consumer Electronics Show, the service aims to complement subscription video-on-demand services for cord-cutters, offering a selection of major cable channels that can be streamed through smart TVs, digital media players and apps
The first few words should explain why there is a lot of press for this new kid in the Chromecast block. Sling is a TV service and that is a bigger deal than an online video sharing website signing up for Cast.
From the official announcement:
Chromecast users can now navigate Sling TV channels on their devices to beam content to the big screen, without ever leaving the couch. This capability makes multitasking seamless, so you can watch your favorite TV shows and movies on Sling TV, all while continuing to use your smartphone, tablet or laptop for activities like texting or tweeting.
Even better, for a limited time, new customers can prepay for three months of “Best of Live TV” and receive a free Chromecast device.* Alternatively, new Sling TV customers using Chromecast will be able to take advantage of a free two-month trial of the “Best of Live TV” package, available from the Chromecast website later today.