The majority of game development done today is done in C++ (With C libraries)
That really depends on how you define "majority". If you count lines of code currently in production your statement is not untrue. However, according to market research, Objective-C is being used more than C++ now for new code. This is predominantly due to iPhone/iPad developers. While most gamers think of PC, Xbox 360, PS3, or Wii games as "the game industry", the reality is there is/are far more money/games in circulation now as a result of cell phones and iOS/Android tablets than consoles or desktops.
With that all being said, your point is not off base. Aside from a few small exceptions, it's unlikely that a game company would hire him without any C++ programming experience. But, C++ is a cumbersome language with many idiosyncrasies. It can be difficult to swallow for people coming from a higher level language. At the same time, game programming provides its own challenges. Most people who already know C++ ultimately give up on trying to become a game developer. Those coming from Java/C# often times give up learning C++ unless it's forced upon them. Combine those two, and it's unlikely someone coming from Java, wanting to learn to make games, would be successful doing so while learning C++ and game development at the same time.
As for DirectX11... Don't do it. OpenGL has a much brighter future on every platform under the sun. ;)
Except for Windows 8 Apps, Microsoft Surface, Windows Phone 7 and 8, or Xbox 360 (and beyond), you mean? But I suppose by "every platform under the sun" you meant MacOS, Linux, iOS, and Android.
The truth is, OpenGL is great for the platforms it runs on. It's also true that DirectX 10/11 are great for the platforms they run on.
Ultimately, they're just API's and have nothing to do with your ability to be a good graphics programmer. If you're learning to program in C#, go with XNA (which uses DirectX 9c) or even SharpDX. If you're down in C++, it honestly doesn't really matter which you choose. They're very similar, and with OGL 4.2 they have almost identical features again. FWIW, I can't stand GLSL, I much prefer Cg/HLSL as a shader language, but that's personal preference. ;) The one thing to keep in mind, however, is there is a significantly larger user base of DirectX. This is mirrored by the number of resources available online and in books. So it's often easier to find the answers to your questions if the questions are about DirectX. Check the forum post counts here on GD.net. OpenGL forum: 4 million posts. DirectX forum: 10.5 million.
Edit: Just look at the latest efforts that Valve are putting in to extend to Linux. This wouldn't be the case if they thought the future was with Windows (DirectX).
Be careful about thoughts/statements such as this. The assumption that a single company somehow has insight into the future of the industry and is thus shifting their efforts is dubious at best. 90% of all PCs are still Windows. Not MacOS, and not Linux. Nobody - not Valve, Bungie, Blizzard, Arena, etc.... are abandoning Windows in favor of Linux. However, as the PC market gets more competitive, smart developers do broaden their user base by taking games to other platforms. Heck, Blizzard has almost always done simultaneous releases for Windows & Mac. And that's with MacOS having only about 5% of the market share. So Blizzard must develop their games strictly in OpenGL right? Nope. Their games use DirectX for the PC version and OpenGL for Mac. You *can* use the OpenGL API on PC, but nobody does, as it's buggy and there are performance issues.
The moral of the story, learn the language and API that will get you up and running the quickest, and will make your journey to becoming a game developer most enjoyable. Once you're there, pick your technologies as surgically as you can. Go to the companies you're most interested in working for, either directly or via job websites, and find out what tools/technologies those companies use. Then become a master of those and you'll stack very well against other candidates when the HR manager or dev lead is evaluating resumes.
Cheers!