Our current stable is very old. Let's stabilize a newer (and qt5-based) one. amd64 only for now. x86 will follow once their qt5 issues are solved. arm never had a stable qt-creator so I'm not CC'ing them unless someone asks. ppc doesn't care about qt5 so they will be dropped entirely eventually.
+1 for that. Qt-creator-3.4.2 on amd64 working flawlessly. What is more, in this version qml design view finally works. In 2.8.1 it had some problems.
amd64 stable
@x86, please proceed.
Let's move on to 3.6.1, bug 581878.