In the longer term, I could see us having the possibility of leveraging Github more. Currently the trac.clfs.org web page has a perception of lacking in functionality, for instance it's very hard to tell someone how to go from the front page of trac to reading the current development version of the books online. Migrating everything from trac onto Github is an option in order to reduce maintenance burden of the trac instance. Additionally, instead of relying on the existing git hooks and existing clfs.org book building infrastructure, we could host the built books on Github pages and use something like Travis to do the building of that. Github pages can also be setup for the cross-lfs group on Github to take the place of what the trac instance has been used for in the past, mainly as a presence on the web and directing visitors on how to read/contribute to the books. The only aspect which I don't feel Github could serve all of the project's needs is with mailing lists.
I don't want to push for moving everything to Github right now, it's a bunch of work and I am not responsible for maintaining any of the trac instance, the book builders, or the mailing list, so I don't really have any skin in this game.