Technically, they are supposedly still supported in CUDA 7.0 provided that you are using GeForce and don’t need any of the libraries. I haven’t actually tried it though because my application requires cuFFT.
Personally I think that having to make your application 32-bit in order to be able to use 32-bit pointers in your kernels is a bit annoying too but that limitation seems to have been there since CUDA 3.0. I should think its quite common that you need >4GB of host memory but have <4GB of memory on each device.
I’d like the option of having a non-unified address space (capped at 4GB per device) and using 32-bit pointers in kernels even for 64-bit applications. I don’t see it happening though :-(