The VS Installer/Launcher has an "Available" tab for quite some time, I have the Community Edition, to show the paid Professional and Enterprise Editions can be downloaded.
In the past the Preview versions haven't been shown on the Available tab. With the recent 17.6.1 update now the Preview version is shown, including a link to release notes.
I know this isn't something extraordinary and earth-shattering, but it makes getting information on the Preview much easier.
This is a nice non-essential change.