Installing it, consolidating the spam accounts, and fixing the situation for people who couldn't use their preferred username.
@Tgr I think we've completed everything related to this? I've used it effectively in merging the various spam accounts, and also in renaming @Koavf 's account.
Yeah, this was done. Turned out to be a little more trouble than expected due to some bugs in the non-CentralAuth parts of UserMerge, but all fixed now.