I've got a different 560ti card (msi twin frozr 2), and so far it's working great in v12. I've seen the other thread and there are plenty of people not having trouble with their 560s. Just chill and wait for your new card mate :) It's entirely likely the problems others are having aren't gpu related.
I haven't tried any of the 3xx drivers yet, but I did have issues with the later 2xx drivers in v11 . I only picked up 12 today so I'll definitely be giving the latest drivers a go in coming days.
I think it's worth mentioning that I also had a 570 gtx at one point with 11 and v11 struggled with that too. V12 however seems a different beast, and it's working great for me so far.
No problem here, PNY Geforce GTX 560Ti. In fact, with the Main Concept mp4 template, there is a rendering hardware selection box at the bottom of the customize screen, and it lets you pick CPU only, Open CL, or CUDA. With CUDA my render times on 1080p footage to 1080p internet widescreen are 1/3 of CPU only or OpenCL.
I am in the middle of a huge project and I am operating on "if it ain't broke, don't fix it" strategy until I ship this out. VPro 11 has been rock solid for me with this driver on this hardware. I won't switch over to 12 for paid work until this project is done.