  We express the diagonals of projective, Grassmann and, more generally, flag
bundles of type (A) using the zero schemes of some vector bundle sections, and
do the same for their single point subschemes. We discuss diagonal and point
properties of these flag bundles. We study when the complex manifolds G/B for
other groups have the point and diagonal properties. We discuss explicit
formulas for the classes of diagonals of the varieties G/B.
