http://www.ign.com/articles/2013/09/02/warframe-confirmed-as-timed-playstation-4-exclusive

Steve Sinclair, the studio's creative director, said, "With how the industry is evolving, this really is the Player Generation. Games are reaching players hands in so many different ways now and Sony gets it, which is why we are bringing Warframe exclusively to the PS4 first. There’s no reason not to download Warframe on day one if you’re an action game lover – it’s free."

probably already known 

Not really news...

This game looks good BTW

most of indies are xclusives for ps4 bcause of MS

usually free to play games want to be on as many platforms as possible/reach as many people as possible, so I expect the majority of those that come to consoles (some simply don't work with a controlpad) to be on both PS4 and X1 eventually

With the recent changes in its Indie Policies I'm sure we will see a lot of excellent indie titles like warframe coming to X1! It is really an exciting time to be a gamer. Also if you haven't checked out warframe do so as you can save your progress for when it does come out. PS4 will do cross play with PC as well I believe.

I didn't read the original article... it is only 3 month exclusive.

Even if it goes to X1, you'll likely need Gold status in order to play it, defeats the purpose of free to play..

If it comes out on One I may have a look at it.