I have recently found that several tech related searches showed spam blogs hosting copies mailing lists ranked higher in the SERPS than the mailing lists own archives.
In most cases the mailing lists were hosted by Google, so the appropriate archive to show would have been Google Groups.
There were some cases where legitimate list archiving sites were shown. That is a good thing because some have better interfaces than G Groups so they deserve their ranking. What I am complaining of is pure copying email to blog post with no threading.