Some observations.
It seems that yahoo is only giving you credit for related links coming in and only 1 credit per site so sitewide links don't work anymore.
The reason I know this is I have quite a few sites. My #2 site has 40,000 bl from every place possible. #3 site has 361 bl.
The #1 site has 450 links as bl.
My #3 site is just reciprocal links and no others.