Download it at:
https://sourceforge.net/projects/inkscape/files/inkscape/0.91pre0/
Tagged in trunk as:
INKSCAPE_0_91_PRE0
The dist directions[1] are outdated, so I'm not confident the package is perfect, but that's why we do pre-releases right? Anyway, if anyone knows a step I missed, please raise it with me so pre1 will be better. I'll try to put some time in this cycle to get these directions up to date, and hopefully streamline the process a bit. I'm hoping to do several pre-releases in support of this.
It would be helpful if packagers could generate binary platform packages from this tarball. If you spot packaging problems (like version numbers that didn't get updated, or missing files needed for builds), please raise these problems with me ASAP.
Bryce
1: http://wiki.inkscape.org/wiki/index.php/Creating_Inkscape_distributions