Recently we were doing a lot of scrambling dealing with Hotmail.com and outlook.com domains being listed on email blacklists SORBS.  While I understand that a blacklist like SORBS is not distinguishing Hotmail.com from a individual company domain, reality sure is.  That reality is that I don’t know many email administrators who can confidently tell their employer that a email site like Hotmail.com has been restricted from emailing anyone at the company, and that’s a good thing.  Its just too broad of a user base.  I personally have no way to argue the point – what can a Hotmail user do to not be on the blacklist?  Very little.  I like SORBS and I want to continue to use it, but I wish they had these large mail domains (yahoo.com, Hotmail.com, aol.com, etc.) in their own blacklist filter.  That way we could still subscribe to SORBS, but not subscribe to the SORBS large mail domain filter, and instead rely on our server-side mail filters to protect us at that point.