Echoe 3 is out, right on the heels of Rubygems 1.2. It supports the new runtime vs. development dependencies, and works correctly with the Rubyforge 1.0.0 gem.
It still supports all the usual features like certificate chains, RDoc upload, changeset parsing, manifest building, and cross-packaging. Documentation is here.
By the way, Rubygems 1.2 seems pretty great.