The leaked ATI Radeon HD 5770 and HD 5750 video cards are official and several hardware sites have published their reviews.
The HD 5770 and HD 5750 cards are attacking the sub-$200 price segment. TechSpot's verdict about the 5770: "At $160 the Radeon HD 5770 appears to be picking up where the Radeon HD 4870 left off. Unfortunately we found the new card to be running slightly short on performance compared to both the Radeon 4870 and the GeForce GTX 260."
AMD had a great showing with the ATI RADEON HD 5870. Looks like things are not so clear with the HD 5770. Read the reviews below to get a picture of the new budget ATI cards.

ATI Radeon HD 5770 And HD 5750 Review Round-Up
TechSpot
Hothardware
Tweaktown
HardwareCanucks: HD5750
HardwareCanucks
Motherboards
Techgage
BenchmarkReviews
HiTechLegion
InsideHW