But what is Sling TV? For $20 a month — yes, twenty dollars — you get access to a lineup of cable networks that includes TNT, TBS, CNN, Food Network, HGTV, Cartoon Network, Adult Swim, the Disney Channel, ESPN, and ESPN2. ESPN is obviously a huge get for Dish and could earn Sling TV plenty of customers all on its own. ESPN just ended another year as TV's leading cable network, and now you won't need a traditional cable package to watch it. For sports fanatics, that could prove enticing. But Dish has hinted that there may be limits on watching ESPN on mobile thanks to red tape from existing deals between the network and Verizon. We'll need to wait for the specifics on that.

There are no contracts involved with Sling TV. No commitments. You can buy it for a month and cancel the next if you're not sold on the idea. And since it's a true, over-the-top internet TV service, you can watch and take it anywhere. This really is TV everywhere; watch it on a Roku box in your living room, and then carry live TV with you outside the house on Android and iOS devices. You can also stream it on your PC or Mac with a web browser. Here's the initial list of exactly where you can tune into Sling TV:

Amazon Fire TV
Amazon Fire TV Stick
Google Nexus Player
LG Smart TVs
Mac / OS X
Roku set-top boxes
Roku Streaming Stick
Roku TV
Windows PC
Xbox One

All of that newfound freedom gives you an idea of why Dish has rounded up a fairly small list of supporters right now. This is new territory that both it and Sony are entering, and popular networks are perfectly cozy with the current system that calls for a cable subscription if you want to watch full episodes and complete seasons of their shows. (Beyond what's on Hulu.com, of course.) There's no AMC here, nor FX and Comedy Central. And none of the big four networks want anything to do with Sling TV at this stage. But instead of negotiating for months and years on end, Dish is choosing to make a go of it now. Give them points for determination, if nothing else. "Our strategy was never to replicate traditional pay TV over the internet," said Roger Lynch, the newly named CEO of Sling TV. Doing so would've resulted in $60 or $70 bundles, according to Lynch. "We don't think that's the right approach.

There's a lot we still don't know about the specifics of Sling TV. You'll be able to pause and rewind live shows, and some will be available to replay for up to three days after they originally air. But others won't, and Dish isn't yet getting specific about names. Exactly where and when will you be able to watch ESPN? Also, Dish says it's got a huge catalog of video-on-demand programming to complement live TV. That includes some internet content producers like Maker Studios. Dish says Sling TV will launch later this month, so it won't be long before you get to try out its take on internet TV. The big question is whether it'll prove worth paying for in addition to Netflix and, eventually, HBO. Just don't count on sharing it with anyone: there's a single-stream limit at all times.

The $20 Sling TV base package includes ESPN, ESPN2, Disney Channel, ABC Family, Food Network, HGTV, Travel Channel, TNT, CNN, TBS, Cartoon Network, Adult Swim, and the "best of Internet video" with Maker Studios. Add-on packs with additional kids and news programming will be available for $5 each.

Lynch said the launch channel lineup was set, but the lineup would evolve over time and other channels would be added. No DVR capabilities or local channels would be available to Sling TV subscribers, but they'd be able to access plenty of on-demand content, he added.

And Dish insist it would wind up a bigger hassle than consumers expect. Instead, beyond the $20 base offering, you can pay extra for "genre packages" that add more content. "You can construct a package that meets your needs rather than the traditional pay TV bundle of big, bigger, biggest," Lynch said. Today, Dish is announcing two of those premium packs: Kids and News. Each will tack $5 more onto the monthly $20 price — and did we mention you'll still be dealing with commercials? Apparently that's one aspect of traditional pay TV that Dish isn't comfortable ditching yet.

No matter where or what device you're using it with, the Sling TV app looks pretty much the same. That turns out to be a surprisingly good thing. The menu system is fast, intuitive, and laid out tastefully. Channels take just a couple seconds to buffer and start playing, and adaptive streaming means you can watch it almost anywhere. Shows will appear in HD on your cushy home internet connection, but will adjust on the fly for slower connections, too. We're just getting out of the gate, but Dish is off to an impressive start.

There's no traditional DVR-style recording here, but you can pause and rewind live TV (with some exceptions). A few networks (not ESPN) even allow you jump back and watch shows that've aired over the last three days. Sling TV offers a healthy amount of video-on-demand content from channels that provide it, and you can rent recent movies like Guardians of the Galaxy just as you would with a typical cable provider. That should help out when the channel list starts feeling a bit thin. There are restrictions, though. You can't pause ESPN at all, so clearly Dish had to make some concessions to nail down that contract. There's another annoying hangup with ESPN, too: you won't be watching NFL games on your smartphone. Don't blame Dish for that one; its hands are tied thanks to an existing rights deal between Verizon and the NFL, but it's still a bummer for fans. Company reps said the restriction won't stop subscribers from watching on a set-top box like Roku or Xbox One.