The addition isn't completely necessary given that iTunes frequently covers the bases for purchases and rentals. All the same, it's still closing a conspicuous gap in availability. Vudu has been available on Roku players, smart TVs, Chromecast and other devices for years -- the Apple TV is one of the few gadgets that can't access it. You probably weren't basing your purchasing decision on Vudu (not by itself, at least), but this might help sway you if you're determined to have as many choices as possible.