My opinion is that we are looking at this backwards. Low latency hardware encoders are now in all dGPUs and APUs to support Video chat and the encoders in most do not use the GPU while all of the older smaller APU codec decoders do use the GPU (using a larger GPU for decoding uses too much power). Why don't encoders use the GPU?
Everyone planned to support low latency game streaming right? If you are using the GPU for a game you can't use it to encode video for game streaming.
So game streaming be it in the home or over the internet has been in the works since before 2010 (See the Leaked Microsoft Xbox 720 roadmap). It's made possible because Video Chat will be a ubiquitous feature which is why Microsoft purchased Skype. We are now seeing the use of those encoders with Game Consoles first and with games because they don't require a common DRM for streaming. We will see video chat eventually replacing the landline phone but the standard for video chat requires encryption and a common DRM scheme between platforms. I believe ooVoo has been delayed waiting on DRM in the PS4.
With Vidipath and the FCC DSTAC replacement for the cable card as well as HbbTV 1.5, TNT 2.0 and ASTC 2.0's XTV; the Smart TV, Phones, Tablets and TV STBs with Playready support will become extremely common and since most can't support Game console AAA games;
casual, WebGL and Playstation Now (Gaikai like game streaming) games of AAA titles will become more popular. Sony and Microsoft will support more casual games and we can see that for the last year or so and with Playstation Mobile.
Apple TV as speculated is only viable with IPTV streaming right. If they don't support Vidipath and sharing media in the home, they are targeting a near future landscape that all the Smart TVs and Vidipath STBs can also support but Vidipath platforms have an advantage given they support the Vidipath transition scheme where the Cable TV DVR is the gateway that converts RF channels to IPTV streams. Apple is apparently also betting on an internet that can support downloadable media vs. blu-ray disk distribution of media...this is also a near future possibility but with the 4K digital bridge, Sony and Microsoft have support for blu-ray disk distributed media till the Internet can handle 4K Ultraviolet without the consumer having to wait 4 to 8 hours for a download.
All the social features we see in the XB1 and PS4 can be supported by everyone provided they also have a dedicated codec encoder and decoder which most have to support required low power IPTV. Nvidia is now providing a SDK for a clone of the PS4 Share Play with AMD to follow. Nvidia has the Shield Game Console/ Android TV STB which already supports game streaming from Nvidia dGPUs on PCs.
Most Vidipath platforms support Bluetooth 4.1 or better and HTML5 W3C extensions for Game Controllers. Apple TV is apparently supporting the same so Games can be streamed Gakai like to Apple TV as they do follow that standard. The difference I see is no support for Playready= Vidipath and sharing media in the home with other platforms.