[link|http://www.x-rates.com/d/GBP/EUR/graph120.html|http://www.x-rates.c...EUR/graph120.html]
This is the 120 day track of the EUR vs GBP.
Even though the pound is no longer formally tied to the Euro or the remaining European currencies, the economic and regulatory ties mean that the pound tracks the Euro closely. So, rather than a drop without reason, it looks like the GBP came back to that track after the upward departure starting at the end of May.
In 1992, when speculators forced a drop like this, it involved billions. Unless Soros & Co are now working with Al Qaeda, if they can harness that kind of money, they're a lot bigger than anyone wants to let on.