There is a POSSIBLE problem brewing with a some of the new Yahoo anti-spam measures.
It has to do with their interpretation & implementation of the DMARC standards.
In a nutshell; Any message that is posted from a yahoo email address will be blocked by Yahoo when it gets resent (by midrange.com) to another yahoo email address.
This issue will probably effect all mailing lists you subscribe to.
for more information.
As a workaround, you could consider getting another email account from Google or Hotmail for your mailing list subscriptions.