This is an unbelievable price for a card that only a few months ago would have cost you over £300!
The 5850 is one generation behind the current 68xx but there aren't any big changes from this generation to the 68xx. The only thing i would point out is if you were thinking about Crossfire(ing) these bad boys the 68xx seem to handle that better.
The Twin FrozR II cooler is one of the best around, it’s super quiet and keeps your card very cool, allowing for massive overclocks.
Review is here:http://www.techpowerup.com/reviews/ASUS/Radeon_HD_6950_CrossFire/21.html
Don't forget you are looking at the 5850 scores though :)
Also comes with Assassins Creed 2 (voucher download), wouldn't be my game of choice but you can't turn down free can you!
It is a pre-order but at this price it's worth the wait!