Based on everything I've recently learned:
For current gaming, the i5-3570k is as much as you need (it's what I just bought yesterday... ). The current games really don't take advantage of the multi-threading that the i7 would give you. It's more for people doing 3D rendering and things of that nature, that require a LOT of computing power. That said, it's not unreasonable to think that games will eventually catch up and the i7 would be the better choice.
Now, I want to mention if you're near a microcenter, they have an awesome deal until 2/10 for the i5-3570k for $189 and $50 off some MOBOs. I got the ASRock z77 extreme4 and the 3570k for $290 after tax, plus a $10 MIR. Pretty sweet deal.
Also, if you think the i7 would future proof you, you could always get that, and add the SSD later. Personally, I wouldn't try planning for the future, because with computers you can only plan for now (as I've heard/read on several occasions). Get the i5, the SSD and rock out!
GL to you.