A few suggestions (maybe for v2):
1) Shouldn\'t the line in the legend animate between \"Supplies\" and \"Receives\"
2) I think the lines should have arrows showing direction of flow - if you do this, provide the option to switch off the path animations
3) I think it would be really good if when you selected, say, Google, you could see all the direct inputs to Google as well as all the direct outputs from Google (i.e. so you see the effect of DMOZ on Yahoo)
4) Taking that one step further, when you select any engine it would be good if you could see the entire family tree (ancestors and descendants) of the syndication channels for that engine
5) Put checkbox [functionality] against the four items in the legend so each can be switched on and off at will