As a customer in the States I was quite interested in what the panel quality would be on this UK rollout. Looks as if the same early stock is being shipped or that Foxconn or whomever is manufacturing these panels can't/won't fix the issue.
The bottom line is that the light leaks can be rectified during manufacturing but someone has decided that this flaw is acceptable. To what degree this issue extends is yet to be known but it's now confirmed in the US and UK shipments.
Not only in us and uk... I live in the Netherlands and I have a bad case of backlight bleeding ( even with lights and at 30% brightness ).
I think it is in the whole world. What I am going to do is to wait 1 week to see how the problem developed and then I will call the apple store to notify my problem but I will wait 1 month or 2 to change it to see if they solve the problem...