That's true in theory; the problem is that OpenCL still feels a few years (or more...) behind CUDA. I have used both, and while OpenCL is undoubtedly the future, CUDA is still by far the better choice for GPGPU today.
The worrying thing is that I've been saying that for the past 5 years, and it hasn't shown any signs of changing. AMD's OpenCL implementation (everything from the drivers to the compiler) are a total crapshoot. With each release they fix one bug, but introduce 1 new one and 1 regression. (completely) innocuous changes in kernel code can make for dramatic swings in the compiled output. All too often AMD's OpenCL still feels like it's at its proof-of-concept phase, and Nvidia (those bastards) haven't released anything OpenCL related since OpenCL 1.1 (which was something like 5 years ago).
OpenCL implementations are too uneven still as well; I have been working with an embedded system lately that has coprocessors and advertises as being OpenCL compatible. The problem is that their implementation is at best incomplete and at worst completely wrong, to the point of not being usable. Maybe in another 5 years OpenCL will be the better choice