Zikula Core 1.5.2 and 2.0.2 are now available. You can access them on the GitHub release pages as usual:
The 1.5.x series will be provided with bugfixes in parallel to the 2.0.x series. This means all bugfixes will be included into 1.5.x as well as 2.0.x. The core developers intend to release future point releases simultaneously, too. New features will not be available until Zikula 2.1.0 though.