Google's problem as I see it, after reading trust rank, is that they focus too much on likelyhoods and stats:
MIT links to you site, you must good pages, whether you have stuff about engineering or Teletubies.
You got a ROS link, so you must've cheated so we'll send you to #300, instead of just ignoring the suscpicious links unless they can be checked. Too broad of a brush, and very easy to fall way off the radar IMO. We're not talking about from #2 to #5, we're talking going to 10 visitors a day.
Basically, from what I am hearing, at this stage of the update.... Getting a link from a solid site, seriously solid Web site, like a reputable newspaper, you are set. Im still looking for gems in these threads - I probably missed a few - but I'll keep looking.
As of 2:54AM (EST) this morning, GoogleGuy posted that Google is "still in flux, reseller. I [GoogleGuy] still expect 220.127.116.11 to spread to other data centers."