Top 5 world botnets generate 80% of spam
I’ve been reading through the most recent Symantec MessageLabs Intelligence Report (April 2010), and one thing I noticed is that the top 5 botnets in the world generate over 80% of the total amount of spam being sent over the Internet, with the top 2 botnets (rustock and grum) getting a combined share of over 50%… And these botnets now spread over millions of computers worldwide (their estimate for the total number of computers that are part of a botnet is between 3.7 and 5.6 million).
The report is full of some pretty cool pieces of information. All in all, quite an interesting lecture. 
