Earlier this week, Microsoft released Windows 10 Insider Preview build 21292 to the Dev channel. It contained mostly fixes for the news and interests feature that appeared the week before, which basically puts a news feed in the taskbar.
Now, we're getting a cumulative update for the build, bringing the build number to 21292.1010. According to Microsoft, there's nothing new in the update. The company does this periodically, but it's just meant to test out the servicing pipeline. Microsoft has to make sure that it can service builds with cumulative updates from time to time, as that's a very major component to servicing a feature update.
The update is KB4601937, and it should show up automatically. Obviously, you can get it now by checking for updates in Windows Update, although there's really nothing here to test out.
Build 21292 is from the rs_prerelease branch, meaning that it includes features that might show up in some future version of Windows, and might not. It's not tied to any specific feature release though.