Hey guys do you all have 2.8? I have two test blogs, one with 2.7.1 and another with 2.8.3. Both xampplite 1.7.1 basically, which is PHP 5.2.9, MySQL 5.1.33, and YARPP 3.0.8 and 3.0.9.
The WP 2.7.1 blog has a lot of posts and Related Posts works well. When I view the wp_yarpp_related_cache for this blog, the Score values are healthy. ALL are >= 1. Most are in the 2-5 range.
In my WP 2.8.3 blog, it has a few posts but more Pages than posts. The wp_yarpp_related_cache for this blog has Score values that don't look very healthy at all, despite a high level of Relatedness. The Score is mostly < 1 with some that are 0! Most are between 0.5-0.9, but some are 17-19. For the 17-19, they work properly and show as Related Posts.
But why doesnt it work nearly as well as my WP 2.7.1 blog? I even hand edited the posts (on the WP 2.8.3) so they have the same Categories and Tags, thinking this would increase the Relatedness to "kick start" the Related Posts action. No dice.
Of course I have tried rebuilding the Cache about 100 times and it doesnt help. I am not using any SuperCache plugins at the moment, either.
I am willing to do whatever it takes to solve this issue and get YARPP 3.0 working properly. Thank you for this nice plugin.
EDIT: Since so many people have commented about 2.1.6 working in the past, I located this old version: http://downloads.wordpress.org/plugin/yet-another-related-posts-plugin.2.1.6.zip
Wow! Instant success! 2.1.6 works like a charm right out of the box. It's a shame it doesn't have the high performance caching system of v3.0 but at least it works.