One intervening factor, imo, is that adding support for C++11 is a complex and unpleasant enough undertaking that few volunteers are able to do it, and fewer of those are interested in doing so. I would guess most language/compiler hackers would rather hack on something other than the mess that is C++ compilation, if they have a choice (and if they're volunteers, they do have a choice). So it ultimately boils down to what companies want to do, since many enterprises are heavily invested in C++. If someone pays their employees to contribute support for GCC, it'll get done, and otherwise, it's less likely. Not that much different from the Clang situation, where C++11 is only really getting implemented because Apple cares enough about getting C++11 support into XCode to pay for it to happen.