It's something I've been thinking about a lot, but I think a game recently revealed by Neat Corporation is the clincher.
The game, called Budget Cuts, sees you playing as an agent infiltrating a mysterious (possibly evil) institution, sneaking down corridors, rifling through office shelves, taking out enemies, and hiding bodies in the trash.
Those points alone make this seem like a VR no-brainer, but what's most intriguing about Budget Cuts is how it gets around virtual reality's motion restrictions. While the Vive will let you walk around, space is still going to be limited.
Budget Cuts gets around that problem by using one of the controllers as a teleportation device; just point to where you want to go and you'll instantly travel there.
It's very Portal-esque, not just in mechanics but also design. I like to think that Valve is working on a Portal game for its virtual reality system, but if not, this will certainly suffice.
This is the swayer - I'm getting a Vive.