http://googleblog.blogspot.com/2010/...ones-that.html
Our early investigation suggests that the "similar" feature will show sites that already rank highly in the same niche
as the site you're searching for... There might be a bump up for items lower on the front page.
The "pure" list of similar sites might also help sites stuck lower in the SERPs since it weeds pushes down many page-relevant results as opposed to site-relevant results.
The "pure" list searchers may be fewer now but their numbers might pick up as this feature becomes more publicized. "Pure" list searchers might, depending on your niche,
make for more targeted traffic which can be a very good thing.
The biggest impact I see so far, from a content generation perspective: this is a great help for list builders/site relationship builders.
What do you guys think?