Don't put all your eggs in one basket and get different kinds of links. In other words have balance. Both low and high
PR links. Links from blogs, directories, contextual links, forum signatures (relevant), articles, Web 2.0 and whatever else you can think of.
The reciprocal links were slammed hard by the Jagger 1-2-3 and Big Daddy updates back in 2005 and early 2006.
Directories got slammed in later 2007.
The Florida update in 2003 smacked a lot of sites hard.
Some sites recover and some don't. Some sites drop in ranking and some don't. So the question is always why?
I guessing that Phrasification and phrase based indexing are a part of Caffeine. Many webmasters are reporting a drop in traffic from longtail search. So, there could be some changes to when the supplemental index is used to return results.
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