I agree, the main page is a little bit outdated. You can mount remotes with where you have only read access, gitfs will fail to push something on the remote, and will put the entire repository in read-only. Right now, you don't have a read-only option, but it would be nice to have :) Great idea about tags and commits directories. It would be nice to specify at mount point, if you also want tags and/or commits etc.

You can fork it https://github.com/PressLabs/gitfs and start hacking around.