Thanks for investigating :) Just thought I'd add that I'm also affected by this, and when I investigated I discovered that the exact selection of users which are omitted and duplicated is relatively stable; that is, if I run the same set of lookups on the same chunks of 100 users, it will almost always be the same users who are missing and duplicated. This can vary slightly over a course of days, but consecutive requests fail in the same way.
I hope this assists the Twitter team in debugging the issue. Thanks, Adrian -- Twitter developer documentation and resources: http://dev.twitter.com/doc API updates via Twitter: http://twitter.com/twitterapi Issues/Enhancements Tracker: http://code.google.com/p/twitter-api/issues/list Change your membership to this group: http://groups.google.com/group/twitter-development-talk
