That is, how many social networks does one need? (in case you don't speak German - you can use BabelFish to translate)
The question is quite timely though. How much time do you spend tweating, linking-in, facebooking, etc...each day? What is this replacing? For me it's television and radio. I rarely watch TV or listen to the radio (much preferring Pandora to replace the latter). Of course, being the 'data miner' that I am, I would prefer that all forms of my media 'learn' based on my preferences. In fact, it actually annoys me when my media isn't 'smart' (or self-training).
Strangely though, I seem to enjoy reading the newspaper MORE these days - it's my one Luddite break from the 'always-on' world. I particularly like the NY Times.
What about you? How has your relationship to media changed over the years?
Wieviel social communities braucht der Mensch?