Founder of Scribr here. We're stoked to see this on HN and curious to see what the minds here think of it.

TheNextWeb has a good article detailing our book here:

http://thenextweb.com/apps/2011/12/30/scribr-preserves-your-...

We also have Timeline-esque features that aren't very public at the moment. We delve into these in our blog here:

http://blog.myscribr.com/post/15036430644