>>11
Most teachers/professors get it wrong. C++ is not object-oriented, it's multi-paradigm. It supports procedural, object-oriented, generic, and functional programming. C is for the most part the procedural subset of C++, or rather, C++ took C and added a bunch of other stuff on top of it, some of it good, some of it less than good. In fact, many of the early C++ standards body people and the people who developed the STL which later got integrated with the Standard C++ Library hated OOP.
Most low-level graphics code is highly procedural and parallel in nature anyway, so even in C++, you'd be using the procedural and/or functional/generic subsets of the language. As for GPGPU, Microsoft is releasing a CTP of Windows C++ 2012 in September, which will have an implementation of C++AMP which supports using C++ across heterogeneous devices like GPUS (it essentially compiles down to DirectCompute code).
I'd suggest learning how to use the other parts of C++ rather then the strict OO stuff. Good C++ code favors class composition over inheritance, avoidance of overuse of virtual functions and exception handling, use of template classes and functions, and not trying to force procedural/functional code to be object-oriented--you use free functions for when it makes sense.
Now's a good time to get into C++ because C++11 is getting ratified in a couple of weeks which fixes a lot of the problems with the language.