As I've said before, all the innovation on the web is happening at the edge. [1] The latest to come from The Edge? Linkbacks. [2]
It's not even a new idea really. Since about 1994 nearly every webbrowser (and certainly all webbrowsers that I know of today) sends a refering link along with the webpage request. You click on the link above, and your browser, in addition to telling the server at www.disenchanted.com that it wants the page /dis/linkback.html it will tell it that it got the link from http://boston.conman.org/2002/5/8.1 (well, most likely from http://boston.conman.org/ until this entry scolls off the front page but that's beside the point) and I've come across sites that use such refering links to generate links back to the previous page.
But what Disenchanted [3] is doing is taking these refering links and linking back to them on the page being linked to in real time (well, subject to certain conditions so it's near real time) and making the those visible on the linked to page. So now that I linked to http://www.disenchanted.com/dis/linkback.html there will be (as soon as two or more people visit that page through this page) a link on that page to this page.
What all these links back and forth will do is hard to say, especially to something like Google. [4] One effect may be a smoothing out of Google bombing. [5] No hard reasons for that; just a gut feeling. Another effect may be to change the shape of the web [6] if enough sites start linking back (although this might take a few years as the technology catches on). There might be effects we can't even predict (who would have predicted the web would look like a bowtie when it first started?).
And while some may question what Disenchanted [7] is doing, I think it's great; I'm approaching Xanadu [8] from the tumblers aspect [9] while Disenchanted is going about it from the two-way linking aspect [10] (although Ted Nelson might not agree with our approaches). That still leaves the problem of transclusion [11] to solve.
[2] http://www.disenchanted.com/dis/linkback.html
[3] http://www.disenchanted.com/
[6] http://citeseer.nj.nec.com/cachedpage/290635/7
[7] http://www.disenchanted.com/
[9] https://boston.conman.org/about/technical.html
[10] http://www.disenchanted.com/dis/technology/xanadu.html