Although it has only just hit technical preview, I have decided to switch my Win 8.1 Hyper-V host over to Windows 10 while testing out new OSD Deployments via ConfigMgr 2012 to see how it fairs.
On the whole it stands up pretty well but one thing I did notice was on my Task Sequence the network adapter I had for the Win 8 Hyper-V host did not work on the Win 10 host and therefore the build failed.
I was unable to locate a .ISO on the tech preview to extract the driver which installed as part of the OS so I used the following useful tool:
The Driver download tool (once installed on a Windows 10 VM inside Hyper-V) allowed me to extract the Hyper-V driver I required and from there I could import this into ConfigMgr and add to my Hyper-V driver package. As you will see below the version of the NIC driver is 6.4 which is (at present) the build type for Windows 10
I would not recommend this for Production Build & Captures incase it layers any untoward issues from a network driver perspective but as a funtioncal build test platform it has held up well so far!