I have just got back from Edinburgh, and I can confirm (in agreement with others on this board), that Bann's (now called UK Bann), the vegetarian restaurant just off the Royal Mile, is one of the best restaurants in town, for for vegetarians and omnivores alike. I have been going there for years and it is as good as ever. Creelers next door is a good fish restaurant. Next door to that is Chocolate Soup - only open during the day - which is a great place for a snack: good sandwiches and great, hearty soups. Thus we have three in a row.
Best wishes to everyone.
I had dinner there last week almost 7 years after your post. It is now called David Bann and it is still VERY good and was reasonable enough inspite of the dreadful exchange rate. Chocolate Soup is still around although it's not next door. Didn't see Creelers but then I wasn't looking. Saw another vegetarian restaurant below street level called Hendersons near Hanover Street. Was wondering about it. Will have to go back and find out!