I do not know the original license of the plugin but since S9Y is available under BSD, I am putting the updates under BSD license. Let me know if I need to change it.
It would be great if it is made a part of Spartacus!!
I think you're doing an excellent job of replicating the adsense ad creation page, but I think you need to pause for a moment and check with Google about how they feel about this.
From looking at your plugin I would say their legal team might have something to say about this, your plugin has gone way beyond a simple plugin to add the adsense code. Be warned if Google decides you are breaking their TOS, you and every site that uses your plugin or hosts your plugin could be targeted by their legal team. That also includes this forum if the Serendipity community is seen to condone or authorise your plugin, so please, be careful and make sure you have Google's permission.
