There is an FAQ list for Blue Moon at http://www.mnemosyne.demon.co.uk/bgames/bluemoon - which also has a few other Blue Moon related things.

It's not approved by Fantasy Flight (I don;t have any contacts there - though if anyone wants to get in touch, feel free) but has been by Kosmos and Reiner Knizia. And my credentials? Discussed in one of the answers.

There is one answer I just had it pointed out isn't right (it basically answers a slightly different question) and I now have another answer to update - it hasn't caught up with this forum. (I think this is FFG's third Blue Moon forum, the FAQ still discusses the - basically unused - second one.) Got a couple of higher priority things to chase, so it'll probably be a little while to update it.

Any feedback, my email address is not difficult to find (on my website or in the FAQ list for starters).