Nope, my PS4 doesn't arrive for a few days and I skipped out on PS3 so I don't have a PS Plus account
Ahh, well all PS4s come with a free Plus Trial (I think), so you'll be able to grab it then. I only arrived back from an overseas trip a few days ago, so haven't tried out much on my PS4 yet. In terms of exclusives, only Killzone Shadow Fall and Resogun.
Shadow Fall's campaign is alright, close to the end now. It's not great by any means - I find the story lacking and some of the design choices strange. It has some ambition, but ultimately fails to deliver for a lot of it. Graphically, however, it is really a showcase for the system - if you want to see what it is capable of day one, buy the game. From what I've heard, the multiplayer is fun, but I haven't tried it yet.
As I said before, Resogun is great. Not much to say here, aside from that it's a highly entertaining side(cylindrical)-scrolling shooter. Short, but very high replay value. If you can, get PS Plus, you need it for online multiplayer, and games like Resogun make it really worth it.