When Apple formally announced plans for an iTunes rental service it was only inevitable that a conflict between Blockbuster and Apple was to occur.  We weren’t entirely sure how this conflict was going to be waged, but now things are becoming clearer:  Blockbuster is developing a set-top box to compete with the Apple TV.“The product would be an offshoot of Movielink, the online film service Blockbuster acquired last year that allows consumers to watch films licensed from the major studios on their PCs.Delivering