Ok guys, I am going to play this on PC!.

[Mhaeric]

Uh,so basically I have to buy a physical PC copy?. With Steam it wont work if I want to use my PS3 account?.

It will work. The only thing that is limited is that you can't link your current account officially to Steam without owning a Steam copy. This is only on the Steam side of things, not Square Enix, so it only affects if someone wants to have Steam track their stats, etc. Since you're buying a Steam copy, you'll be able to do that just fine, and you can link your current PS3 account to it via Square Enix's Mog Station website. There should be an option at the top of your Mog Station page to add or link the service. I don't think you want to add a new service account, but add a service within your current service account, just to be clear.

Mog Station