Grid Layout for Post Template

grid is going to ship in the post template block as a layout variation for post template. There are currently no real possibility of configuring for the child blocks, which is what really gives grid all of its flexibility. The exposure of actual sort of grid layout control is kind of limited, but it is using grids. So technically, yes, there is one block that is shipping with grid layout. However, that hasn't been marked stable yet because what we have currently has a very basic version.