This is a minor maintenance release, primarily fixing an issue which could result in bad SQL if you created or update an item in your database, and explicitly provided a null value for one or more of your fields. This could occur sometimes when you for instance had a frontend that was automatically scaffolded, and you removed for instance a string value and set it to empty string, which would result in the field being explicitly set to null.
In addition, there are some minor fixes to other parts of the system, and some minor cosmetic changes, such as using the new logo for touch icons, etc - But the above bug fix is the most important parts of this release. If you had problems when setting a value to empty string in your frontend, this release will fix that problem.