I think to a certain extend, spammers are in a fix. With spam filters improving so much, most of the spam gets trapped.
As spammer find new methods to break through these filters, spam filters are constantly improving too. Now it may seem that spammers are at a losing end.
Spam filters work by detecting a pattern in your email to see if that email message is an advertisement or something to cheat you.
Take a look at one of the spam I received in Gmail (want a Gmail invite?).
From: Sara Helms
To: dew [at] beconfused.com
Date: May 19, 2006 3:34 AM
Subject: composed_(Click to enlarge to view contents.)_
I received 3 of these mails already, all the same content, just different subject and from address.
By using images, it poses problems for spam detectors to read what is in the text. I don’t think any spam filter deploy text recognition abilities. They’re just too resource intensive.
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