I would rather rent a Digitally Distributed movie for a few dollars than get ripped off buying the physical media.
But I am the first to admit this is all dependant on your viewing preferences.
HD movies are really just for the videophiles at the mo. I am quite happy watching a Low/Standard Res movie and I hardly ever watch anything twice.
I guess its what makes more sense to you. For me Cash is King.
If Blu Ray players drop sub 50 Bucks and the movies are available at a price point similar to DVD I may switch. Otherwise I'll sit the "format wars" out.