Twitter from the command line in Python using OAuth - step-by-step howto
jmillerinc.com
jmillerinc.com
This is much more difficult for a user to understand ("why can I give twitter my password, but in this client here, I have to do this strange dance? What am I supposed to do now?").
In most of the client apps, the issue of having to enter your password is a non-issue as there's no need for a third-party to know it.
In the case of desktop apps, IMHO, OAuth does nothing but makes the lives of both client developers and users harder.
http://developers.facebook.com/docs/authentication/
Soooo much easier.
Who knows what they will do in the future.
I don't know of any easy way to programatically grant OAuth access.