For a few days, the users/show method offered look up based on a user's email address. So short-lived was its documented availability that we removed it without much fanfare. This thread [1] has mention of this deprecation.
Recently, there has been quite a bit of discussion on this feature's reinstatement on and off the list. Issue 353 [2] covers this request. The use of the method was largely as intended; people were discovering account connections based email addresses. This made integration with other networks and applications trivial. However, there was a significant amount of traffic that was using this parameter for evil. In either case, the adoption was minimal (we did not receive a complaint that the deprecation completely broke someone's application). The rationale for deprecation was to protect our users' privacy. We do realize the large amount of value that this parameter creates for application developers. However at this time, we are working to identify a solution for the spammers that caused the deprecation. One suggestion is to grant trusted applications access to this parameter. Since our answer to trusting applications is OAuth and it is still in beta, we will not be able to devote the resources necessary to bring this parameter back at this time. If you are developing an application that could benefit from an email-based lookup, please star the issue [2] accordingly. 1. http://groups.google.com/group/twitter-development-talk/browse_thread/thread/ac80b4fdf8eb742a/692b27b8ebd07268?lnk=gst&q=email+parameter#692b27b8ebd07268 2. http://code.google.com/p/twitter-api/issues/detail?id=353 Thanks, Doug Williams Twitter API Support http://twitter.com/dougw
