ncm suggests:
Now that there are stable links in your diary page to those accounts, the spammers can come back any time and re-establish them, and get good Google tracking without the "nofollow" annotations found in the "new members" list. I have noticed that spammer accounts with no text attached often slip off the bottom of the "new members" list undeleted. There would be no searchable Google-preferred reference to those accounts without your links. Probably you should so annotate your own links.I see no continuing value in these links now the accounts are deleted, so I have changed the anchors to bolds. I do think anchors mean the accounts are deleted rather quicker than they would otherwise be, and unfortunately you can't give Advogato links nofollow annotations: StevenRainwater's html munger drops rel tags in anchors.
I'm still not concerned about "stealth" accounts that neither certify, nor are certified, do not post diary entries, nor are linked to on the new members list. Why should anyone care what text they have, or what nofollow links they make? Note that recreated accounts do appear on the new members list, so receive no less scrutiny than accounts with fresh names. Cf. e.g., new account rosecole, Spam Rating=12.
In the unlikely case that some use is found for these junk accounts, it should not be too difficult to run a filter on the Advogato account database and Apache logfiles to dredge them up. Or bloat the robots.txt file with a list of Observer account pages...
FWIW, compare the results for the following two searches: