Skins
Skins are not now and will never be in Gaim's default GTK+ UI. GTK themes, however, are supported, as per the Gaim FAQ. This confuses many users, so an attempt at explanation follows.
Themes allow you to change font size, font face, the color of different elements of the UI, and sometimes their shape. All of this is perfectly reasonable, and encompasses the range of configuration that most users are requesting. Skins go beyond this. Skins allow you to move and possibly supress different elements of the UI that the programmers have added for specific reasons.
In so doing, skins create a support nightmare. The developer, talking to the user, cannot be sure that the user sees the same interface. Is it a bug that the user cannot see how to change font size, or is the user's skin suppressing that widget? This is an unacceptable situation.
Conversely, while themes allow some sillyness, for instance setting the background to the same color as the font, the results are relatively easily foreseen and avoided by theme authors. Further, by using the existing GTK theme mechanism, we gain two advantages:
We don't have to write it ourselves. Were we to write our own mechanism, we would be adding overhead in both the run time and the time necessary to debug.
We have a built in way of debugging theme problems, by checking if the same bug exists with other GTK programs.
Lastly, since GTK themes only allow acceptable modifications, we do not have to worry that a user isn't seeing part of the UI because it is either showing or not showing because of our code.
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