From the 0.8.8 release onwards, the qore library may be used under either the GPL 2.0LGPL 2.1, or MIT licenses.  

When a C++ program calls qore_init() to initialize the library, a license argument must be passed to the function.
When the qore library is initialized with the LGPL or MIT licenses, no modules tagged as requiring the GPL license can be loaded.
This means that qore can be used in commercial applications, as long as the library is initialized with qore_init() with QL_LGPL or QL_MIT arguments, indicating that it is to be used under the terms of the LGPL 2.1 or MIT licenses, respectively.
Qore scripts/programs can be licensed under whatever license the author wants; they are not restricted by Qore's C++ source licensing.  Qore scripts/programs may have no license, commercial licenses, or anything in between.
Note that Qore example code and modules released with Qore is released under the MIT license.