In the talk I will illustrate some recent developments of the theory of sets of finite perimeter in infinite-dimensional Gaussian spaces (Wiener spaces). Since in this context the usual differentiation theorems (based on Vitali or Besicovitch covering theorem) fail, the notion of measure-theoretic boundary and of codimension-one Hausdorff measure have to be properly understood. In particular I shall focus on recent papers by Hino and Ambrosio-Figalli on the extension of De Giorgi's representation theorem of the perimeter measure to infinite-dimensional spaces.