It's an odd proclamation. Even if it's an open API, I don't think people will write hamburger throwing apps for linkedin because that's not what people go to linkedin for in the first place. Most people log in there to do business-like things. Apps like 'throw hamburger' probably wouldn't be added by most, especially in light of being seen as unprofessional, in industries where it still counts. So only the apps that help business-like things will be added.

However, that's not to say working people can't be inane and juvenile. My guess is if there was a "watercooler" app where you can anonymously gossip about your coworkers (what truemors should have been, imho), or if it was something to count #meetings vs # of bathroom breaks, there might be an uptake on that.