I also love that Possession is getting a nerf. It's not the best card in the world to begin with, but now it's even not as good. ![Smiley :)](http://forum.dominionstrategy.com/Smileys/default/smiley.gif)
It's getting a buff. Previously, you could counter Possession by going for Goons and Bishop and Monument, but now if you do that, your opponent will get the tokens instead when he possesses you.
I haven't skimmed the whole thread yet, but we don't know if there will be more VP generating cards than debt cards. It's too soon to know for sure whether it's a buff or a nerf. It's possibly a nerf against Guilds coin token cards too since they can't be stockpiled for use across multiple possession turns.
Possession is going to be weird with debt because the possessee can be made to buy like 10 debt cards in one turn. Then the Possessor can just focus on playing Possession while preventing the opponent from buying anything and pulling the same trick when they themselves are possessed, because of all the debt. The lesson here is to avoid +buy cards in a Possession game with debt cards.
So like, people have been listing the hundreds of little ways that Mission rocks. I imagine debt cards will be strong for similar reasons given how dramatic their effects are.
I like that the debt cards avoid the King's Court problem where "first one to get it wins". These cards are always accessible so long as you have no debt, similar to Chapel. I imagine these were ideas that were too difficult to price fairly without the introduction of debt.