It appears the forum spam protection has locked everyone out of the forums, from what I hear it won't allow new registrations either. So for now, the idea is to open a Github Repository to allow people to open an issue on Github for questions to keep the community alive. It seems Gene the admin of the forums is missing in action, so hopefully it gets resolved eventually.
Thematic has a new 2.0 version coming out, it is currently in beta.
You can download the new version here - https://github.com/ThematicTheme/Thematic/archive/develop.zip
This version incorporates a bunch of newer HTML5 features to the code allowing for a more modern looking code base. There is now a responsive version of the child theme, it currently looks identical to the original Thematic theme. Karin Taliga (http://invistruct.com/) from the forums is the one who has done all the work to get it updated.
The new 2.0 version is backwards compatible. If you have the new Thematic beta theme installed, make sure to check in your WordPress Admin in the "Appearance > Theme Options" section of the menu. There you will find a "Restore Legacy XHTML1.0 Doctype", with this checked, you won't notice any changes from the old version of Thematic. If you do want the new features, make sure that box is unchecked. :)
If you want to help or contribute, make sure to go to the actual Thematic Theme Github https://github.com/ThematicTheme/Thematic
Thematic Questions? Create an issue on GitHub.