I don't know that B&B, but it is in a great part of Venice. And, you'll be able to get to the Guggenheim when it opens. You'll also be near Ai Gondolieri, which is a really nice rewstaurant that--unusual for Venice--doesn't serve fish.
Robert, A Slowtalker, by the name of Phoebe, mentioned it in the post below dated August 22, 2004. I don't think she ended up staying there. (I hope this links properly)