there are five interviews scheduled for Mental Models for GIMP.
You can see them here:
Interviews will be held October 2nd-6th.
Interviews will be recorded and transcribed and will
be available online.
There will be more interviews covering the GIMP's user groups
according to the product vision.
The aim is to construct a mental model based on the interviews.
For more information about the method, see
Gimp-developer mailing list