I've been the recipient of well meaning warnings from folks on this board recently.
The info was nothing but a hoax.
If there is NO LINK to McAfee or Norton in the warning you can safely regard the warning as spurious.
As a Norton A-V user, I'm surprised that they don't have a mailing list such as McAfee's.
If you would like to subscribe to the McAfee.com Dispatch, click here.
http://dispatch.mcafee.com/sub.asp?s=22
It's worth joining!