In the beginning, there was a huge outpour of support for Twig and a lot of people helped with the conversion. However, as various issues blocked it, most people have understandably disappeared. Now that Twig is available during Drupal installation, we can continue with conversion of core theme functions and templates.
We’ve got about 2 weeks to finish up conversion (mid-April) so we can move on to things like implement Twig’s autoescape functionality and consolidate similar templates and theme functions.
The meta conversion issue tracks all of the conversion issues we are working on, and you can also check the Twig TODO list for areas where you can help. Anyone with a web browser that knows HTML can contribute, and if you know Git basics you can help even more. We need help manually testing patches, rerolling patches, tweaking documentation, fixing automated tests and more.
There are several patches awaiting review, many simple patches that can be created by front-end developers, and some sticky issues we could use developers’ help on.
There are always several people on irc.freenode.net in the #drupal-twig channel available to help you get involved. Please come by and see what you can do to help. Look for @steveoliver, @Cottser, @Fabianx, and @joelpittet for help getting started.