Since I am out on vacation, I'll do a quick quick summary.
He plotted data showing that for his tests, there is a strong value to "fresh" or new links, the time before they receive any true PageRank and other metrics from Google. The fresh links can be used to give a site a temporary boost in rankings in Google, until Google determines the true value of those links.
I have seen signs of this for years. I felt it had two do with two things. (1) The fresh link value that Branko describes in his post and (2) the value of that link being on the home page of a site, and not deep down inside the directory structure. So when this site links out to an other site, that site might see a temporary boost in rankings and then those rankings may fall.