Can I ask why? It has been both in the past and was changed back – because of multiple user requests – to number (for very good reasons which I hope someone here will remember!)

i just dont like people knowing in what order people sign up to my site,plus there are easier sql injections with user numbers rather than names.

neither is security, except by obfuscation…

not sure how displaying a user id is any less secure than a login id…  no better, no worse injection risk – you still need a true security hole to get in…

Also if i choose to hide admins/moderators from members list(silent ones) all someone has to do is just go through the numbers,i just prefer usernames instead 

understand, but dont see it changing in near future…  more folks have clearly requested it not be login names since that can also lead to brute force login hacks..