The other obvious options, besides the existing Facebook page (which isn't too bad) are a Google group/hangout/whetever or a blog like you can get for free on Wordpress.

Anyone like to comment on the advantages and disadvantages of each? The obvious disadvantage of Facebook is the way it restricts access to content in unpredictable ways to coerce people into signing up. Google keeps messing about with their API to make their services inaccessible to people who don't have exactly the right sort of machine, OS and browser (Blogger is the absolute pits for this). Wordpress generally requires you to sign up before you can do anything much.