It looks like all of the AMD HD 6950 cards appear to be ready for unlocking, at least for now. According to Wizzard from Techpowerup, it is a matter of a simple BIOS flash and your HD 6950 can easily turn to an HD 6970. AMD even made the process a bit easier as AMD included the dual-BIOS feature on its HD 6900 series cards and if something goes wrong you can always go for the recovery/factory protected BIOS.
It looks like AMD didn't use the fuse locking on its HD 6950 cards and it is a simple BIOS update that makes the card switch from its 1408 to 1536 shaders and even reach HD 6970 clocks. For now, the unlock is possible on all HD 6950 cards and not just a handful of review samples.
Nice news for all those who snatched the HD 6950 and it looks like these will be selling quite nicely in next few days. You can find more details here.