The KDE project put out the second release candidate of the upcoming KDE 4.3 on July 9th. This comes only a few days after the first RC was available. This release is codenamed 'Canteras' and it is specifically intended for testing purposes and bug reports only.
KDE 4.3 will include many Plasma improvements, several changes, PolicyKit integration, Geolocation services and many bug fixes.
According to the official announcement, KDE 4.3 is expected at the end of July.