A future Android update could break tons of root apps
The Android root ecosystem is an enormous community of developers and users dedicated to unlocking all of the potential inherent in Android. The ecosystem has myriad custom ROMs, with at least one for most devices; and, for those not confident enough to flash a custom ROM, there are tons of root apps to extend functionality. Unfortunately, many of those apps may become unusable if recent code commits make it into a future Android update.
Android developer Chainfire has found code committed to the master AOSP tree which " prevents the unconfined domain (everything you run through [superuser] by default) from executing files located on the /data partition". The trouble is that many root apps will extract files to the /data partition, and these changes will break functionality in those apps if these changes are released in a future Android update.
This will undoubtedly cause quite a few problems, but Chainfire does also say that there are a number of workarounds which can be used to restore functionality. Unfortunately, there isn't one singular fix that can be implemented by all developers with root apps, so developers will have a quite a bit of work to do in order to get ready for these changes.