It should be fine for those games at medium or so settings and you'll get slightly less visual fidelity than the next gen consoles but hey, for the price you're paying for it it's pretty decent
Depending on your other components, you could just upgrade to another mainstream card in a few years (depending on market conditions and card pricing) which would be many times more powerful than the consoles by then
But as of the term "future proofing" the 7770 isn't going to last you too long and will start to chug behind in a few years (even on low settings)
Thanks for the advice, I only plan to have it for around a year so I'm now confident it will dome fine.
Check this video of a comparison between a high end gaming PC (i7+GTX 780), the PS4, Xbone and a budget gaming PC (AMD quad core+7770) and you'll see that the 7770 system performs admirably at its pricepoint
http://www.youtube.com/watch?v=IHogNolObqk