I would say there's a good possibility of someone making the PC version of the Pinball Arcade work with the Rift even if TPA doesn't offer native support. I recall there being a third party app that helps make non Oculus games work with the device. Native support would be amazing though especially with DK2 and the consumer version offering positional tracking which would allow for players to lean into a virtual table either head on or from angle just like in real life.
I did hear that motion sickness is gone in DK2 thanks to the low persistence OLED 1080p display being used.
I've had a developer kit 2 on preorder since the first couple hours of preorders back in March so hopefully I'll be able to try it out soon. Super pumped for the Rift in general. Coolest piece of tech in years in my opinion. I was able to try out DK2 at PAX East this year and was blown away by how cool it is to use.