Fossil's new(ish) semi-automatic bidirectional interaction with Git mirrors has finally made Mercurial replaceable for me. However, it is hard to ignore that the IT world has mostly decided to settle with whatever is the most commonly used right now, no matter if it is actually the best solution - so at least when it comes to DVCS, the war seems to be over.
How does that interaction work? Last I checked, it wasn't great or it was too much of a hassle (I don't remember exactly).
cd $FOSSILDIR
for f in *; do
/usr/local/bin/fossil git export -q -R $f
done
Importing works... similarly. :-)