It's all about the games.
SCEE's SVP Michael Denny told CVG that he is confident that the PlayStation 4 will have a launch line-up that sells the console to consumers. He said:
With PlayStation 4 what’s exciting is we can see the strength in depth of titles come through – not just in first party but third party, and I really believe PlayStation 4 will have the strongest launch line-up we’ve ever had.
Although it's a bold statement, it doesn't hold as much weight as you'd expect. All three previous generation PlayStation consoles had only moderate software libraries at launch. The PlayStation 2 relied heavily on SSX, while its successor looked to Resistance: Fall of Man to pull its weight.
Nonetheless, Sony has a long history of offering dynamic, award-winning titles—exclusive or not—as its hardware begins to mature. Any betting man would be ludicrous to bet against Sony's ability to bring system sellers to the PlayStation 4.
For reference, below are the PlayStation 4 games that are expected to release within its launch window.
Deep Down (Capcom)Destiny (Bungie)Diablo III (Blizzard Entertainment)DriveClub (Evolution Studio)Infamous: Second Son (Sucker Punch)Killzone: Shadow Fall (Guerrilla Games)Knack (SCE Japan Studios)Watch Dogs (UbiSoft Montreal)The Witcher 3: Wild Hunt (CD Projekt RED)The Witness (Thekla, Inc)