I might make a longer response later, but I wanted to comment on a few things quickly:
On 8/13/07, Tangotango tangotango@ts.wikimedia.org wrote:
On Aug 14, 2007, at 12:00 AM, Anthony wrote:
But I think en.wikipedia.User:Anthony and fr.wikipedia.User:Anthony should be able to get along. I'll probably win the eventual conflict between us, as fr.wikipedia.User:Anthony doesn't have very many edits, but I don't think there should have to be a winner. The two of us have gotten along perfectly fine without SUL.
In the grand scheme of things, far more users are going to benefit from being able to log in to Commons with their English Wikipedia accounts. I sympathize with the situation you are in, but I think this is more a technical thing than a who-gets-what-username thing.
It is possible to let people log in to Commons with your English Wikipedia account without SUL. First, attach the two accounts using a global identifier (could be a number, and doesn't have to necessarily be seen by anybody). Then, have a login page on commons with three fields - username, wiki, and password.
How do you attach the two accounts without knowing the global identifier? Log into your commons account and type in your en.wikipedia username and password and press "attach". Or log into your en.wikipedia account and type in your commons username and password and press attach.
Commons account usernames could even be used as this global identifier. That'd simplify the login stage - each wiki login would have a spot for username and password and a drop down to select the local wiki or commons.
None of this implies SUL, because users are not required to use the same local username on every wiki. And in fact, doing things this way is going to be a required step before SUL *anyway*, because there has to be a transition period while working through the conflicting usernames.