I didn't see any in the keynote snippets I read, but since this is a more surface-oriented, infotizement I didn't really expected. Someonw who is there find out what the deal is, please. Will it be enabled in Leopard? Will it support turning all on/all off, and/or a mixed mode where you can have it on but manage individual objects manually? How does it deal with issues such as circular references? Any word on performance hit?