However, a recent review of YouTube and Netflix in my own digital living room (yes, not the average home) reveals that the pair of apps continues to update their list of capable devices in a pretty aggressive fashion. In the image below (Netflix) you can see they have added Amazon's FireTV, the Xbox One, and the latest Samsung TVs (at least). Full disclosure, I don't have a PS4 to test against. It did not detect my Roku. My Amazon FireTV stick requires the user to select a casting mode before the apps will detect it.
Of course the "rest" of the casting apps (HuluPlus, Flixster, etc) still only detect the Chromecast device itself. A likely scenario is that Google and YouTube will continue to push the envelope (they require new apps to enable casting to get onto their device) and others will follow.
The other likely result is that the value of casting as a feature for sharing 2nd screen content will grow but the value of the Chromecast device itself will diminish over time.