Nokia has announced that starting with version 4.5, Qt will be available under the LGPL 2.1. From the announcement,
The move to LGPL licensing will provide open source and commercial developers with more permissive licensing than GPL and so increase flexibility for developers. In addition, Qt source code repositories will be made publicly available and will encourage contributions from desktop and embedded developer communities. With these changes, developers will be able to actively drive the evolution of the Qt framework.
This exciting change, made with consultation of the
KDE Free Qt Foundation, should encourage KDE and Qt use among commercial and proprietary developers and makes the philosophy of "Qt Everywhere" complete.