netmeg - 4:01 pm on Jul 18, 2012 (gmt 0)

From now on, you can invite trusted colleagues or partners to sign in to your AdSense account and also run reports, manage payment information, and generate ad code. In addition, this new user management feature can also be used to change the Google Account login linked to an AdSense account.

[adsense.blogspot.com...]

Finally! Added my partner this morning; previously no way to do it without giving him full access to all my Google stuff.

There are two levels, standard and administrator. I think the only difference is that only admins can add more users.