Much like Nintendo did with the Wii U, you will be able to play your PS4 games on the go using the PS Vita console.
This announcement was made by Sony during its PlayStation Meeting earlier today. It was said that if your kids are using the PS4 in the lounge, you could always play your game using the PS Vita via remote play.
I could not tell from the low quality video what PS4 games look like the PS Vita, but it might look similar what current PS Vita games do. It was shown in real time that Knack is playable on the PS Vita.
Sony plans to make every PS4 game playable on the PS Vita.