I've written custom rules which search the body for refifast.biz and gozealgaming.com and add large scores to them.
These seem like "The spams of the future". I don't know how else to target them.
Is this the right way to solve this problem? Piecemeal highly-specific rules that I write by hand to address certain individual spams?
One word... SURBL.
The surbl system is very good for dealing with these "clean" spams that have a link to a spam website in the body.
And of course, these "spams of the future" are dealt with by default with "SA of the future" aka version 3.0.
If you need it now, there's an add-on for 2.63 available, see details at http://www.surbl.org/
