There's a broken wrist in England so far, and several arrests (not counting the punches and kicks, etc). No deaths as far as I can tell, and it seems to be all over now.
Just for interest: These sort of sales do not exist in Germany. In my opinion, they never will. I don't think there would be much left of the country after, if they were. They are the greatest bargain hunters I've ever come across.
As far as I ever saw, the French don't do it either - purely for reasons of lack of style, I would think.
In Spain, they'd all start chatting and forget they were there to get a bargain - plus, they wouldn't want to mess up their clothes.
In the Netherlands, people are just too laid back and nice to start pushing and shoving, and they always have some great bargains anyway.
Just my opinion. Happy to be corrected by anyone who knows these countries better than I do.