[cs702]

Agree. I would add three more qualities to your list:

* Fully programmable, via a nicely document Lua interface: http://www.darktable.org/lua-api/index.html.php -- you can automate all kinds of workflows.

* Truly innovative, with clever new features unavailable in other applications, including Lightroom. For example, five years ago they added a powerful new "equalizer" module: http://www.darktable.org/2011/11/darktable-and-research/ (google "darktable equazlier" for usage examples).

* Always improving: I've been using it for years and the developers keep finding ways to make it better all the time.

Congratulations on another great release!