Categorized by Yahoo! = penalty?

[cslhypnotech]

(long time reader, first time poster. great content here, appreciate everyone's work)

Recently our main web site has dropped for our main keywords on Yahoo! from ~#1-3 to ~#15-17. The bossman is not too happy about this and frankly, neither am I. At first I thought Yahoo! just hadn't crawled us in a while since the title and description it had listed for us was out of date.

Then I noticed that we had been placed into the Yahoo! categories. Sounds to me like it would be a good thing being listed in their directory, but why the penalty in SERPs? Is this the price you pay? Will it ever be updated?