The next version of the Next Generation Sync Client will be released in waves. I received the first Update on a Windows 8.1 device, today the same on a Windows 7 client, and I think we will have also this new version 17.3.6915.0529 also on Windows 10.
I will say Thank You for all new subscribers of my blog and for theses people here my advice: NO, you do not have to download this new Update manually and install the new sync engine over the old one. This process will be fully automatic. Every day, the NGSC is looking for a new version (and if Microsoft has set this version for release). If the answer is Yes, a file with name OneDriveSetup.exe will be downloaded, started and installed. Only on old and slowly machines you may feel, that an Update process is working and it takes a little while, until you may work with all functionality.
What has been changed?
Unfortunately I’m not able to write something about it, because there is no information about it. You do not find anything in the changelog, but I know, that Microsoft will publish some information about this new version.
So there is a huge step form the last version 147.3.6799.0327 to the new 17.3.6915.0529, but 116 version were built from Microsoft, but not released. For users running Windows 10 (with Creators Update), they may count 99 versions.
You will found an overview about all versions here.
I will have some more information here at this blog post.