Sometimes you need to customize post counts for individual categories.
You can set values for each category as you wish..
When adding category, you can specify post count for that category..
You can use automattic install from your extensions page or you can install it manually.
Unzip archive, upload category-post-count folder to the wp-content plugins directory.
Activate the plugin through 'Plugins WordPress...
If you didn't change it after installing WordPress, it has to be 10.
It can be changed from Settings > Reading page of your Admin area...
Does it have to be same values for posts and feeds..
Browse the code, check out SVN repository, or subscribe to the development log by RSS...
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