Rotate it 90 degrees then we can have some gore!
Haven't looked in to CUDA much only because it was highly restricting (only working on NVIDIA cards). OpenCL, however, was developed as a kind of "sister language" to OpenGL and they mesh quite well together.
Really, the main thing I like about it (and the reason why I keep pushing it on you) is that you only write a single set of almost-identical-to-c code and tell it which platform to target. The compiler creates the binaries for the platform(s) you want to use so you don't have to worry about writing multiple slightly different copies of the program.
Not to mention, it's cross-platform. Runs on OSX (Snow Leopard), Linux, and Windows. Can be compiled to execute on multiple CPUs, GPUs, and DSPs (Digital Signal Processors) or a combination of. There's also rumors that PhysX chips will be added to the list as well
For me, the major downside is the lack of recursion