What I found most amazing was that email-attached malware made up almost 30% of the total email sent!
If I'm reading their summary right it looks like a big piece of that spike might have been the botnets trying to re-establish themselves. (Quoted from your link just to show what I'm looking at): "Zombie activity also dropped significantly after Rustock was taken down, but large increases of enslaved computers became evident following the malware outbreak at the end of the quarter."
Does anybody know what a "Parked domain" is? I'm wondering what they're referring to when they say this: "Parked domains were the website category most likely to contain malware."
Interesting read. Sure is a lot of spam out there.