According to Herb Sutter in this article it was "partly an oversight". The article contains a nice implementation, and makes a strong case for using it:
template<typename T, typename ...Args>
std::unique_ptr<T> make_unique( Args&& ...args )
{
return std::unique_ptr<T>( new T( std::forward<Args>(args)... ) );
}
Update: The original update has been updated and the emphasis has changed.