Planet13 - 8:10 pm on Jul 13, 2011 (gmt 0)
My personal opinion (really more of a guess) is that this is more evidence that the death of Page Rank has been exaggerated in these forums.
I really think that big brands get big links simply due to the fact that they are so well recognized, and thus ordinary people are more willing to link to them.
also, if you look at some of the major SEO software sites out there, they seem to boast how many big name companies are using their software. If they ARE truly using their software, I would imagine that they are using it for link building as well.
Again, just a wild guess. No scientific evidence to back it up.