There are plenty of things you can do to help out with Myrmidon. The
Todo list describes items which still need to
be done. Of course, since this is an open-source project, there's
plenty of scope for experimentation, and you can pretty much make up
your own items to work on.
Some things that are worth reading if you do want to get involved:
There is no Ant 2 or Myrmidon mailing list yet, so direct any questions
or comments you have to the ant-dev mailing list.