Considering the stress the tree is under putting roots down into its new surroundings, these blooms are pretty good. They aren't six inches as advertised, but they're about four and I suspect they'll be larger and more plentiful next year. And they definitely come out later in the spring -- this tree probably came north from a warmer Tennessee climate, so next year it will bloom a couple of weeks later here in Ohio. Still, our red dogwoods have already dropped their petals, and the white one is on its last legs. Both of them bloom before the leaves come out, but the Venus dogwood already had large green leaves before the blooms appeared.
And the blooms are very different. Here's a comparison (which wasn't easy in the evening sun) -- at left is one of the remaining blooms from our "regular" white dogwood (3"), and at right one from the Venus dogwood (4").