eMarketer reports that email spam levels have fallen over the past year, and that the breakdown of spam, by category, has also changed.

The most common types of spam subject matter should be no surprise to anyone who uses email: mortgages and loans, pornography, lottery/gambling (including phishing emails), gift cards and medication (in that order). Mortgages and loans account for over one-fifth of spam e-mails, down from one-third in Q3 2005. Pornography became more common, while medication-related spam fell from 18 percent to 12 percent.

The data show that spam accounts for slightly less of all email sent (down from 74 percent in December 2004 to 57 percent in December 2005). However, alternative venues such as instant messages, chat sites and blogs are the likely new homes for the deluge of spam.

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