Sony has confirmed its Playstation Now service will add PS4 game streaming on PCs in the near future. It currently only offers games from the PS3 back catalogue. Coming so soon after Microsoft's announcement of Xbox Game Pass it's clear Sony views Microsoft's close integration of Xbox and PC as a threat to the dominance of its PS4 system.
It's not an unexpected move, however it does offer PC gamers new and interesting choices.
Microsoft's offering runs on the Xbox only - for now at least. There's no confirmation that Play Anywhere titles will be included in the subscription. Sony has taken a step further. Playstation Now becomes a Netflix-like service for PS4 games on PC or PS4.
Will it materially affect buyers choices in the future? Probably not. However Microsoft and Sony are in a battle for supremacy which dictates each maintain feature parity with the other.
Being able to extend your gaming to your PC is just the latest area where this is manifesting.