In the South End, The Gallows is one such spot. It has been open since this past summer and I am fairly certain that it has filled its serving area solidly every night since. Somehow, it has not been affected by the recent closings of neighboring restaurants that have plagued the area.
I would think it has something to do with the slightly gothic/rustic style that is a nice change from the usual swanky, black and white, which is the current trend in South End restaurants (Union Bar and Grille, Pops, Aquitaine...etc)
A quick look at some of their dishes could also prove further evidence as to their success and popularity.