Hi, We recently converted our site to use twitter oauth over basic authentication and automated the exchange of credentials so that we didn't have to keep multiple workflows around nor bother our users.
Here's a helpful script in ruby which makes use of the great twitter and mechanize gems. (this is obviously a little bit brittle, so I wouldn't rely on it for anything other than batch conversion) Also, the script makes multiple http calls to twitter and is subject to timeouts, backhoes, and other ill effects, so expect it to be slow and fail often. We loaded up pending conversions into a persistent transactional queue and ran multiple processes in parallel. http://gist.github.com/108144 - Jon