The real gem in the command line options is are the export options. These are a command-line interface to load up an SVG file and export as another format in a non-interactive format. This allows for the inclusion of vector format conversions in scripts.
Since the well-known image conversion utility ImageMagick does not have vector-to-vector format conversions, this is a very useful tool.
Particularly, this is an issue when using Inkscape (or other tools that use SVG) to create images for LaTeX documents, where one of EPS, PDF or PNG is typically used.
To convert an SVG file to an EPS file use
inkscape -f file.svg -E file.eps
to a PDF,inkscape -f file.svg -A file.pdf
and to a PNG,inkscape -f file.svg -e file.png