That would be awesome for consumers, but probably bad for the manufacturers. People would have a choice, but then again when buying the cheaper version would feel that they are buying something worse, the inferior product. That would probably cause many people to wait with their purchase till a significant price cut to get the better version. I know that's what I'd do 
Still, it would be a great idea to have the same game (from the very same disc) running on two different versions of the hardware with different performance, yet sharing multiplayer, etc. This would be a great way to extend the time of a generation. In fact, Sony and MS could do that even this gen. Instead of releasing a simple Slim, make a Slim and a PS4+/Xbone+. I would be all for it, if it finally gave us 1080p/60fps.
Still, I think from the business perspective it's best not to confuse the consumer and keep only one version of hardware. Sadly.
Wii U is a GCN 2 - I called it months before the release!
My Vita to-buy list: The Walking Dead, Persona 4 Golden, Need for Speed: Most Wanted, TearAway, Ys: Memories of Celceta, Muramasa: The Demon Blade, History: Legends of War, FIFA 13, Final Fantasy HD X, X-2, Worms Revolution Extreme, The Amazing Spiderman, Batman: Arkham Origins Blackgate - too many no-gaemz :/
My consoles: PS2 Slim, PS3 Slim 320 GB, PSV 32 GB, Wii, DSi.
