Glade 4.4.0 is shortly to be released, which makes a move from Qt 4.8.x to Qt 5.1.1. Although the porting has not been as bad as the Qt3 to 4 fiasco, there are still several issues that have caused problems and although the regression testing has picked up some of these, others are more cosmetic and/or tricky.
So when it's released (Win32/64 platforms will come first as they still represent two thirds of the downloads) please back up the current 4.3.58 that I hope you are using (if not download it now!) and try out carefully.
Win32/64 platforms are up now and Ubuntu 64 bit is just uploading. It's a slow process for the Linux versions as the VM's have to be updated to support xcb which is now required for Qt 5.x, and the new version of Qt compiled etc etc…