Marc Mutz, a Qt/KDE developer, has written a blog post calling for C++11 to be utilized quickly by Qt, KDE, and other free software projects. Mutz wants C++11 to be adopted as quickly as possible for the new features of this language and to avoid this language becoming stagnant or only slowly deployed over many years. Mutz also calls for C++98 support to be dropped as quickly as possible.
There's already been other blog posts responding to this proposal. It's extremely unlikely that C++11 will be a requirement for Qt 5.0, which is due for release next year, and that it's also unlikely for KDE 5 / KDE Frameworks. However, optional support for C++11 may come sooner.