"How many Mac applications still support OS X 10.2? 10.3? 10.4? Half of the web doesn’t work anymore on KDE 3.5′s Konqueror."
I'm not familiar with the author's product and can't say whether C++11 is the right choice for him, but I wouldn't consider the constant API churn of OS X or the constant web standard and web standard extension churn to be a good argument in favor of anything.