The development version of Kubuntu is now reached version 13.04 Alpha 1. This next Kubuntu uses Raring Ringtail as its codename. So, whats new on this Kubuntu 13.04? Technically, there are a lot of improvements have been made to this version but I will not explain here. You may read the full release not of the Kubuntu 13.04 Alpha 1 here.
Slightly, Kubuntu 13.04 is not much different with Kubuntu 12.10 in term of GUI. You still find the old Kubuntu 12.10 style on this Raring Ringtail. But the installer is well upgraded so its easier to install Kubuntu.