Long-standing (though not very accurate) blacklist APEWS seemed to be down for the count. Their website at www.apews.org has been down since March 15th, according to David Ritz.
My recommendation to mail administrators is to stop using APEWS. But then again, was anybody using APEWS recently, anyway?
For history's sake, here's a link to the article I published long ago, explaining what to do if you find yourself blacklisted by APEWS.
APEWS was previously down for three weeks in August, 2010.
Update: APEWS appears to have returned somewhere around May 1st, 2013.
It goes down, it comes back up, it goes down again, it comes back up again. At this point I think we'll just call it a status of "?????"