I'm a fan of C++ but I think that for production Java and OpenGL will lead for compatibility/readability advantages of both.
... Says the absolute dearth of Java / OpenGL games besides that, I have to question the sanity of anyone who believes that Java or OpenGL is more compatible or readable than alternatives in practical terms, despite promises of the contrary. The readability of both is perhaps a matter of taste, though.
For the kinds of things that C++ is really good at there really is no viable replacement--maybe D someday, or Rust, but certainly not any kind of Java or C#-like productivity language. The trouble with C++, really, even moreso than C, are the number of potholes you'll encounter on a daily basis. I think this stems mostly from the fact that so many subtleties are afoot that almost no piece of code does precisely what it appears to do, and any piece of code that does perform its purported function precisely probably bears only a passing resemblance--at least, with the way most people write C++. For example, probably any 10-20 line function of C++ that does anything at all non-trivial and which compiles with exceptions enabled probably has 20 or more ways of exiting, often not safely when an exception is thrown.
More idiomatic, best-practices C++ code which relies on proven patterns and facilities like smart pointers, standard containers and standard algorithms is both safer and more productive, but for some reason -- sometimes technical reasons, other times cultural ones -- C++ users are in practice somewhat resistant it seems. Its an additional learning curve that many people percieve as being "outside" the necessities of the language itself -- perhaps because the learning curve of the lange is itself so large. Languages like C# or Java, I think, will always be ahead on the productivity and safety curve, owing first to a shorter legacy, a smaller and more-homogenous language, and the conveniences and safety buffers that their runtime environments supply -- which is a bit like bowling in the bumper lane.