Mass Action: Assign Users to Group

[Matthew]

Does anyone else need to mass-assign a bunch of users to a user group? Have you considered how to approach this?

I want to be able to search for an email domain (already possible), and then selectively assign those users to a User Group.

I can see how to insert a new menu item into the Mass Action menu, with a callback. But I'm stuck on how to pass a user group ID to the callback function.

One idea would be to pass the array of user IDs generated from the mass action, to the callback, which would then generate a new page, with a dropdown of the available user groups at the top and the list of users in a table below. You select the group you want to assign the user to, and click 'Submit'.

But might there be some way to do this directly from the list of users?