theoretically, as the yen falls, the dollar should strenthen against all currencies, but in the long run, the british government is doing a better job in its economic policies than the US....so theoretically, in the long run the pound should do much better than the dollar.....but who knows what will happen in practice....so many factors are involved....
but if i were a betting man, i'd bet on the pound vs the dollar...the US govt just doesn't seem to have the intestinal fortitude to do what it takes in dealing with the debt crisis, while the british govt does....