This means, they give each other a
Currently all service providers (known to the author) offer their Bookmarking Servers as a free service.
Read more on this topic in: [en.wikipedia.org/wiki/Social_bookmarking Wikipedia:SocialBookmarking]
The problem with this kind of a "free bubble" is, that it might not stay free for all the time. The providers refinance their free service with advertisement or they credit it on the speculation, that at a later time, they can sell their complex hardware/software/service package to a big player like Google.
Now this doesn't solve the fundamental problem, but escalates it ownly.
As soon as Social Bookmarking Communities and their technology evolve to such a level of sophistication, that advertisement becomes superfluous, the bubble will burst and the illusion of a free for all paradise dissolves abruptly.
What do you suggest to do? Ride it to hell or prepare a soft landing? -- [fridemar]