Lots of nay-sayers on this, I wonder how many have expensive gaming rigs and hate the idea of having wasted their money. Then there are the hundreds of thousands of organisations and people that have a financial interest in hardware. There is bound to be backlash against this.
This is already working. There are services that provide this already and work reasonably well. Price will come down with competition as more companies and maybe even ISP's get involved. Instead of spending big bank on the latest gaming setup it will go to this so price isn't that much of an issue.
There are many technical hurdles to overcome before this can fully compete with the best physical hardware but with focus put on these services, displays, reliable and fast internet then the end of the PC, consoles and any kind of box will come and to think otherwise is misguided.
It is worth giving this some serious thought and consideration before investing in new hardware if you have a decent internet connection.