It seems to me that many bigger C++ libraries end up creating their own string type. In the client code you either have to use the one from the library (QString, CString, fbstring etc., I'm sure anyone can name a few) or keep converting between the standard type and the one the library uses (which most of the time involves at least one copy).

So, is there a particular misfeature or something wrong about std::string (just like auto_ptr semantics were bad)? Has it changed in C++11?