The Symantec story is about the large drop in spam traffic over Christmas, but in fact the chart shows enormous fall in recent months generally, under 20% now of what it was back in August 2010.
Suggestion is that this is not because spamming has become bad business for spammers sadly, but simply a change of focus in upcoming spam campaigns. We live in hope.
Not clear what kinds of spam this is tracking, email only, or blog comments too ? I mention that because subjectively I’ve much less spam in the blog comments queue during the last year – 60 per 30 days rather than 200/300 ? FaceBook and LinkedIn suffer a different kind of spam – friendly spam from any group or page you “like” sending every update to ever member – just lazy use of very crude common-denominator apps.