AnandTech tested both the Radeon HD 7870 GHz edition and the Radeon HD 7850, they conclude AMD has taken firm control of the $200+ video card market, but that the question is: for how long? The Radeon HD 7870 1GHz Edition is about 9 percent faster than a GeForce GTX 570, the new card costs about $25 more but it also has as an advantage that it's cooler and quieter. The Radeon HD 7850 on the other hand is the fastest 150W TDP card in the market, but at $250 it's nearly $50 more expensive than the GeForce GTX 560 Ti. On average, the 7850 is about 9 percent faster than the GeForce GTX 560 Ti, but in some games it's the other way around, in Battlefield 3 for instance the GTX 560 Ti wins by about 8 percent.
Another opinion comes from The Tech Report, they note the new Radeons are good performers that are way more power-efficient than the previous generation, but complain the cards are held back by somewhat conservative pricing. It seems like AMD is keeping some (price) ammunition in its pocket until NVIDIA's 28nm Kepler GPUs come out.