Imagine you have a host of aggregation services like Friendfeed, Tumblr, Suprglu, Lifestreams connected to each other, such that each one is reading from your various feeds and republishing the content.
Now imagine a disaster where one of these services, say Twitter, suddenly, because of some flaw, exposes your private messages.
It's like a Tsunami that cannot be controlled! Your private data would flow into various input streams in a matter of seconds and there is no turning back.
Things will only get worse with activity feeds and Beacon.
The bottom line is: Be careful about where your data is going and what data you put online.
