It looks like LinkedIn has been looking at which Facebook features it can steal. LinkedIn’s newsfeed does appear to actually be news rather than friend activities, however, and tries to work out what the user might be interested in. It’s only in beta at the moment but it’ll be interesting to see if it does work. Personally: I’m not convinced, because I read all kinds of disparate rubbish and I don’t see how any newsbot can work that out.
Alongside that it seems that the API is starting to make an appearance too, at least to some partners. How OpenSocial it will be is hard to tell at the moment.