It was in the road plan so I'm assuming it's time Sony did it:

According to our sources, the announcement is planned for August 23rd, with a launch in Belgium, Netherland and UK in the first place, with United States and Canada following one week later

http://www.gamekult.com/actu/le-playstation-now-bientot-sur-pc-A167103.html

Makes sense this was always in the works. When it happens it's going to make PC even better than it already is. Being able to play all the PS4/PS3 titles plus everything on Xbox. The only downside will be having to use keyboard and mouse for online gaming.

Did you mean PS2/PS3? PS4 won't be coming for a few years.

Good to hear. If it's to become the Netflix of gaming it needs to be on every platform especially the pc.

Well I assumed they would be adding PS4 games once they venture on to other platforms. They are only on PS4 right now so makes little to no sense to add PS4 games. I have no idea how long it will be until they add PS4 games did they say one way or the other?

Oh so Sony has already said PS4 games wont be coming to PSnow?

don't worry when PS5 release 

So the only thing exclusive to PlayStation is PS4 games? Not even all PS4 games but certain PS4 games? Is PSVR usable on PC too?

PSNow has nothing to do with the console market. The only reason it was on the Vita/PS3/PS4 was because it makes sense to launch the service on your own devices. Sony WILL NOT allow PS4 titles to be available for a long time. They want to sell PS4s.

And don't discount the possibility of PSVR going to PC too.

I don't see why this would hurt PS, and I don't see many pc gamers jumping on this either, but I am sure some will take a license for one or 2 months to finish some games they missed, like uncharted or the last of us.

Overall this seems like a logical step for sony. They want as many people as possible paying to play their old games.