Sven,
Something that I'd like to see (if it hasn't been done yet) is to make the popup progress dialog dockable. How feasible is that?
Well, we don't want to make it dockable, it should be embedded in the associated dialog. Yes, that should definitely be on the list for 2.2.
What if there's no associated dialog? I have some plugins that call (lots of) Gimp functions non-interactively, with no image display. The result is that the progress dialog is constantly being created and destroyed. Things would be much neater if it was (optionally?) just part of the main toolbox window.
-- David Hodson -- this night wounds time