site authentication

I have just signed up for google adsense (hopefully they won't ban me this time round)

but is the site authentication part important. I have some sections not open to the public, so is it important that I give google a username and password or something?

google can't use cookies, so giving it a board login is pointless. That login they offer is for htpasswd style folder protection.

I've had 0 issues with private forums showing relevant ads. it's javascript, so it runs on the users' browser anyway... not froma bot