Yes, If you were trying to make it to Maxwell and skip Kepler like i'm doing (SLI GTX 560 ti's) I would also agree you could make it another 2-3 years. But just make sure your power can handle it. That card will Handle 1080p games excellent. You may not get excellent fps on all games then your gonna need a better card. but it holds it's weight on most all new games.
Well I bought an XFX HD5970 Black just over 2 years ago and it's still fantastic. OK it was the fastest card in the day but with the way it performs now I have no intention of upgrading until after the 7000 ATi or Kepler. By which time it will be at least 3-4 years old. I'm thinking if you want high settings for the next 3 years you might be best with a 580 but good luck anyway!