Search Engine Watch Forums Moderator, DaveN, feels that Google is targeting directories, by that he means, devaluing the links from directories. He bases this statement on the large amount of recent data he collected. For those not familiar with DaveN, he is someone who might be referred to as an "algo chaser." In other words, he is one of the guys that make the search engines better by exposing loopholes within the algorithms.
Of course, most of us would just push off such a statement. Google, Yahoo, Ask, MSN and all the search engines recommend getting quality inbound links. Some even say that you should get them from directories. Heck, Yahoo and MSN promote paid directories, Google uses the ODP.
But if one would think about it more. The way this industry has been going follows this sort of pattern. Search engines like variable X. Some SEOs look for ways to exploit the variable X. Search engines have to move away from liking X and then move on to Y. The process repeats, over and over again. So maybe DaveN is right.