If the result is Yes, it wouldn't be a move to keep GBP as it is but to have our own currency. This currency would just be called the Scottish Pound and start off at same rate as GBP.
That is not the position of the Yes Scotland campaign:
http://yesscotland.net/news/common-sense-currencyI should've said "might/could" instead of "would." AFAIK these are options and nothing has been set in stone? Mark Carney saying any move to keep the pound would need to be negotiated on independence being obtained but that he would implement whatever came out of negotiations.