My opinion on video card upgrades always comes back to what resolution you are gaming at? If you are at 1920x1080 or below, Id probably stick with the 570 for a bit longer. Very few games currently are going to use more than 1gig of video ram at 1080p resolution and below. The further over 1080p that you go, the more a 670(I'm assuming you meant 670 and not 680, as 670s can be had for close to $300, 680s are like $450+) is going to be a difference. At a resolution like 2560x1440 a 670+ is going to run circles around a 570, but at lower resolutions the gap isn't nearly as drastic. At 1080p you might see a 15-20% performance gain in going up to a 670, while at 1440p it might be 100% gain or more.
It's a tough call on the best use of that $300, as your PC is still pretty solid overall. I'd maybe think about sitting on it for a month or two and see what prices do in 2013. SSDs just keep dropping further and further. 2nd quarter 2013 should see the release of the next generation of video cards, AMDs 8000 series cards should start hitting the market in Spring, and thats bound to drive down the price of everything else. You might see the price of video cards in general drop significantly in a few months in anticipation of a new generation. Basically, I have a suspician that unless the $300 is burning a hole in your pocket, if you wait a couple months you might be able to get BOTH a 670 and a 256gig SSD or something. I love my 180GB Intel SSD thats in my new computer, and while having your OS on a SSD is a game-changing experience, having a game on one isn't nearly as big of a deal. How often do most modern games stop to load anymore? Something like Skyrim or Far Cry 3 really only stops to load when you fast travel, otherwise the world loads seamlessly as you play and move and the SSD doesn't really enhance that any. It isn't going to give you better framerates. Yeah, you save a few seconds when you first start the game, but your playing experience really isn't enhanced much.
