Earlier this month I mentioned OpenSocial, and Decius replied:

If the same people show up in every social networking website, doesn't that defeat the individual value of each community? Do you really want to "import" your linkedin connections to facebook? Sometimes its useful to maintain different sets of associations in different contexts.

On that thought, here is Tim Berners-Lee:

People running Internet systems had to let their computer be used for forwarding other people's packets, and connecting new applications they had no control over. People making web sites sometimes tried to legally prevent others from linking into the site, as they wanted complete control of the user experience, and they would not link out as they did not want people to escape. Until after a few months they realized how the web works. And the re-use kicked in. And the payoff started blowing people's minds.

Letting your data connect to other people's data is a bit about letting go in that sense. It is still not about giving to people data which they don't have a right to. It is about letting it be connected to data from peer sites. It is about letting it be joined to data from other applications.

It is about getting excited about connections, rather than nervous.