Read on for a quick overview of spam trends and events in the first quarter of 2009.
Spammers have clearly rallied following the McColo takedown, and overall spam volume growth during Q1 2009 was the strongest it's been since early 2008, increasing an average of 1.2% per day. To put that number into context, the growth rate of spam volume in Q1 2008 was approximately 1% per day – which, at the time, was a record high.
This year we've seen the payload viruses spread out across every day of the week, with no immediately obvious pattern in their distribution. It's difficult to say for certain what prompted the change, but one possible explanation is that spammers switched tactics because they weren't seeing the success they'd hoped for from the focused attacks.
Of course, payload viruses have also seen a recent spike overall -- in the month of March we saw a 9x increase from February. This pales in comparison to the highs we saw last summer, but it may indicate a developing trend that's worth keeping a close eye on.
Posted by Amanda Kleha, Google security and archiving team