About the releases:
Kate and KWrite are part of KDE Applications, which are released typically 3 times a year en-masse. The text editing and the syntax highlighting engines are provided by KDE Frameworks, which is updated monthly. New releases are announced here.
* The release packages contain the latest version of Kate and KDE Frameworks.
** The nightly packages are automatically compiled daily from source code, therefore they may be unstable and contain bugs or incomplete features. These are only recommended for testing purposes.