I just landed in San Francisco and took the BART directly to BarCamp San Francisco. I grabbed some coffee, some beer, and some North Beach pizza from the common areas, and then landed straight in an intense session about microformats.
I'm hearing lots of actions that at their base sound like publish and subscribe actions. But we're trying to stick at the UI layer – one of Messina's stated goals was actions that are the same across sites for the same type of data. e.g. a Greasemonkey plugin that could do "add as contact" when given an hCard, no matter which site you are on.