The gifting cities thing has become a hot topic atm. Personally i don't see anything wrong with gifting cities as such, if someone wants to trade cities or give a city for gold or whatever thats fine with me because that is in the spirit of the rules, but if your doing it to deny someone capturing a city or to save someone being defeated then that is not right. I think we are all experienced enough in playing the game to know whats right and whats wrong.
As for the whole vassel state thing Regentman and DaveMcW have going that's there buisness, i see nothing wrong with it. Its a very shrewed move by DaveMcW to save some maintenance costs while collecting gold although personally i wouldn't make the agreement myself, i wouldn't see the point of hanging around with one city giving all the production to someone else