No, Netflix isn't an early adopter of 4K resolutions. "Super HD" is simply Netflix's term to help hype its support for 1080p.
Unfortunately, Netflix isn't kidding about "select" ISPs. Only Netflix subscribers with Cablevision or Google Fiber will have access to the exclusive "Super HD" and 3D streaming.
But it's not Netflix's fault. In 2012, Netflix launched Open Connect, allowing ISPs to manage the flow of content to their customers. So, for now, Cablevision and Google Fiber are the only ISPs that have opted to support "Super HD" and 3D streaming.
There are currently a select few devices besides PCs that are compatible with Netflix's "Super HD" streaming, which include the Wii U, Roku with 1080p, PlayStation 3, and Apple TV with 1080p, though more devices are promised to come.