Now that Qt 5.3 is past its beta, Digia developers took some time to issue a release candidate of Qt 4.8.6. The Qt 4.8.6 point release will be the first official Qt4 tool-kit update in the better part of one year.
The Qt 4.8.6 update incorporates various recommended bug-fixes for those still using software that's not yet been ported to Qt5. The 4.8.6 release should come in April and isn't the last planned Qt4 update. Digia is tentatively planning to release Qt 4.8.7 in H2'2014 with additional bug-fixes. These releases are not about back-porting major features from Qt5 but mostly about stable fixes. Qt 5.3 meanwhile is set to introduce Web Socket support, new Qt Quick improvements, major work on the Android and iOS ports, Windows Runtime platforms support, and other improvements.
More details on today's Qt 4.8.6 RC1 release can be found via this Qt mailing list post.