The global AbuseLog entries are showing the wrong usernames. E.g. compare http://deployment.wikimedia.beta.wmflabs.org/wiki/Special:AbuseLog to http://en.wikibooks.beta.wmflabs.org/wiki/Special:AbuseLog
This is because it's using the afl_user field to look up the user name from the local (meta-wiki) DB, which leads to wrong (or non-existing) users, because the ID given is for a foreign wiki. Caused by me in Gerrit change 34032 (sorry :().