Mechanize is a core part in quite a few of my projects lately and the fact that it hasn't been modified in over 2 years has been very worrisome.
There are lots of edge cases out there on websites. Mechanize has built up years of fixes and workarounds for these, I hope that MechanicalSoup can learn from these the easy way rather than waiting to make the same mistakes again.
I also hope that this repo grows into a bigger community of support, not just one person contributing (who could leave / get bored at any time). Looking forward to following this!