Social Networks Feeds getting duplicate posts

As social networks started to gain space in the net, they began to overlap with each other, that is, user of one service are also user of other. Soon they had to understand and recognize the other social networks their users were at, too!

Mashups, pipes and other kind of combinations allowed a single post to one service to get “propagated” to the user´s registered social networks.
As users start to link their social, those mashups start to spread the chaos.
Let me put a simple example.
One of the first social networks I joined was Delicious.
Later on came Facebook, and at that time I´ve also joined FriendFeed which allowed me to post several of my other feeds´ posts right through Facebook too.
Now Twitter. And now Delicious allows you to Tweet directly every bookmark you post.
This is confusing, but that´s exactly as it grew up.
To get a clear picture see below how my feeds for these services ended mashed-up.

Sample Feeds Map

As you can see from the graph, the same delicious post gets posted twice into my Facebook stream.
Feeds´post would need a unique identifier understandable by all your subscribed services (or something alike).
Otherwise, since those services don´t currently have that intelligence, it is up to the user to check it´s own streams under each of his/her social networks,to identify for the duplicate posts and rearrange the services subscriptions to each other, acoordingly, for that duplication, not to occur.

Feeds Map after fix

As a result of that re-arrangement, I had to stop publishing Delicious and my blog posts through FriendFeed. Instead, let them go through Twitter and then through FriendFeed, all the way to Facebook.
That way, posts will show up only once on my Facebook stream.
At least until someone (it could be myself!) finds another solution. But this can get even worse…