Rooting is a process not everyone who uses an Android device takes part in. It's a fairly specific niche group of people that actually root their devices, and utilize many of the wonderful root required apps that are out there to make using a rooted device that much easier. The great thing about all these root required apps is that they can make the root experience better, by offering you tools and features that help with things like backing up app data, and even help by downloading newer versions of Gapps for future use when flashing to a new ROM. While many of us use these apps on a daily basis, that might soon not be possible as the next version of Android could end up rendering some root required apps useless. At least, momentarily.
Chainfire, which is a developer that is responsible for a popular app that lets you enable other apps for access to root rights, points out on his G+ page that the upcoming version of Android could cause problems with root apps. As he states, "a recent commit to the AOSP master tree" is what will prevent anything that gets ran through SU by default from executing any file that is located on the /data partition. He goes on to point out that not all root apps use this particular process, so not all root apps will be affected. However, a good many of the root apps that exist extract the binaries and scripts to app-specific Files or lib directories, which of course are located on, you guessed it, the /data partition.
Now this doesn't mean that root apps will be broken forever, and because it could still be many months before the next version of Android gets released by Google, there is plenty of time for developers to find work arounds and come up with a solution to fix the issue before this problem could even affect the apps in the first place. He points out at the end of the post that it's a good idea and it might be proactive to notify any developers who are the authors of your favorite root apps. While it's likely that many of them are already aware of the potential future issue, some of them may not be, so sending a quick little email with the link to Chainfire's G+ post couldn't hurt. Worst case scenario is they have already seen it and they'll just dismiss it. It's always nice to see Google attacking the very real problem of security, even if it produces a little more work for developers in the long run.