Hi,
I've just committed a patch (trunk revision 10062) that replaces the bitmap selector list (in the preferences) with a file selector. It reuses the existing "open" dialogs (the file type filter are set to executable files - or everything, on Gnu/Linux and OSX - and the preview disabled), but the change doesn't affect usual "open" or "import" operations. I hesitated to create a new specific dialog, but found it more logic to reuse the existing ones. The initial goal of that patch was to make it work on Windows (see Bug #26261, Edit externally doesn't work on Windows, https://bugs.launchpad.net/inkscape/+bug/262617), but it also adds command line arguments support (as far as the image is the last argument...). It should work on Windows (native dialog and GTK), Gnu/Linux and OS-X (thanks ~suv for your help!).
Don't hesitate to comment. Regards. -- Nicolas