Just an FYI so people are not surprised. When I rolled Windows 10 Pro on top of an install of Windows 7 Ultimate today I noticed that there is now an entry in the Device Manager for the WD My Cloud. Here is some info from the Device manager entry.
Device Manager
Western Digital NAS
WDMyCloud-XXXX
Location: http://192.168.1.XX:9000/TMSDeviceDescription.xml
Driver Provider: Western Digital
Driver Date: 4/30/2013
Driver Version: 2.2.01
WDMyCloud-XXXX
Location: http://192.168.1.XX:49152/nasdevice.xml
Driver Provider: Western Digital
Driver Date: 4/30/2013
Driver Version: 2.2.01
So far no problems accessing the WD My Cloud with Windows 10 Pro. Mapped folders to the My Cloud were carried over without issue. Haven’t rolled Windows 10 Home yet onto another PC with Windows 7 Home to see if any unexpected issues crop up with the WD My Cloud under that OS/PC.