Qt 4.8.5 was released this morning by Digia and it offers nearly 400 improvements over the previous Qt 4.8 release. These improvements include security updates, error corrections, and other bug-fixes. There were 35 fixes to Qt Core, 64 fixes to Qt GUI, 8 Linux/X11 fixes, an upgrade to WebKit 2.2.4, and other enhancements.
More details on the Qt 4.8.5 release can be found via this Digia blog post. Meanwhile, for the latest upstream fun, Qt 5.1 is almost finally out the door.