If memory serves, Rcmdr already does this for you using rgl. That may be limited to the models that Rcmdr fits, though.
On the other hand, it gives you (fast !) scrolling, zooming, ... which lattice cannot do.
I do love rgl! But there are times when 3-D plots in lattice are useful too - you can write your own function which you can pass to the 'panel' argument to lattice functions. For instance,
mypanel <- function(x,y,z,...) {
panel.wireframe(x,y,z,...)
panel.cloud(x,y,z,...)
}
wireframe(myGrid$z ~ myGrid$x * myGrid$y, xlab="X", ylab="Y", zlab="Z",
panel=mypanel)
The last function you call can be wireframe() or cloud(); in either case since panel.wireframe() and panel.cloud() are called within the panel function the result should be the same.