Planet13 - 8:35 pm on Aug 23, 2011 (gmt 0)
I have seen some really good benefit to above average links from related sites. I've also had to teak my internal link structure to maximize it though.
For instance, a page that was ranking nowhere for my main keywords moved up to #25 back in May and then moved up to #8 in July. Right now, it is the sixth SITE in the SERPs, but is in position #8 because two sites above it have two pages each in the SERPs (the #1 site and the #2 site both have their index pages listed and a second page listed).
But my backlinks were all gotten by hand by me and it has been very time consuming. Once I get higher in the SERPs (above the fold), I expect to receive more "natural" links (i.e., links that I don't have to beg for).