When I 'upgraded' to W7, I discovered this HomeGroup "feature". I was able to ignore it somehow, and network back into my remaining and still protected XP devices at that time.
It would be nothing short of stupid and irresponsible for M$ to drop a networking capability now or at any time in the future. I'm expecting that they have just dropped the HomeGroup thing and left the facility to network in there as before.
As for the rest of the 'upgrade'? I can't see anything worth getting excited about. It seems now that the Windows operating system is destined to be like the home created Basic programs of old - never quite finished. always something which can be touched up or fiddled.
Thanks for the warning ....
FOR