Discussion and communication about the graph-tool project are done through mailing list conversations. Information regarding subscription and archiving is available at the mailing list's webpage. Alternatively, it may be accessed via its Nabble or Gmane interfaces below.
The mailing list is also fully accessible through Gmane, which means you don't have to subscribe to post and receive messages, and you can also access it with a news reader.
Nested view: http://news.gmane.org/gmane.comp.science.graph.graph-tool.general
Blog-like view: http://blog.gmane.org/gmane.comp.science.graph.graph-tool.general
Gmane info page (includes RSS feeds): http://dir.gmane.org/gmane.comp.science.graph.graph-tool.general