Tor 0.2.1.23 fixes a huge client-side performance bug, makes Tor work again on the latest OS X, and updates the location of a directory authority.
alpha fixes a huge client-side performance bug, as well
as laying the groundwork for further relay-side performance fixes. It
Tor 0.2.1.22 rotates two of the seven v3 directory authority keys and
locations, due to a security breach of some of the Torproject servers:
Tor 0.2.1.20 fixes a crash bug when you're accessing many hidden services
at once, prepares for more performance improvements, and fixes a bunch
of smaller bugs.