I just thought about this a few minutes ago when discussing the companion gaming app and the whole "Brb. Bio break" thing.
Sony has stated that all PS4 games must support streaming to the Vita. This would mean that if you have to go to the bathroom you could take the game with you. If someone else wants to watch TV, you could stream the game to a Vita and keep playing your character without interruption.
I can understand people's concern that this will mean that PS4 games will have to be lower quality, but in reality all that's happening is basically a lower resolution video is being streamed to the Vita (Like Youtube), and the inputs from the Vita are being streamed back to the PS4. It would require very little raw power from the Vita itself, and therefore should run fairly well as long as you don't go too far from your PS4 or wireless router. And this functionality will work with any PS4 game as long as it doesn't require the camera.
Will this influence any future PS4 owners to buy a Vita, or do people feel it's still not worth the buy?