There is no question cash is king right now but I have to admit that I'm very concerned about the near term future of GBP and eventually all paper currencies. Interest rates are simply irrelevent, safety is paramount.
The only physical paper currency I would probably consider holding is the Swiss Franc.
I'm considering holding onto a cash balance in USD using Goldmoney.com for a while. When the time is right, I can just transfer all the dollars into metal instantly at the click of a button for speed and convenience.