When a world appears in the Games category it sometimes shows the Public player count and sometimes shows the Total Public + Private player count.
The number that appears depends on where the value was last cached by the client:
  • When a world is first loaded in most other categories, the Total Public + Private player count gets cached in the client as the displayed player count in world lists.
  • However, the results that are first loaded into the Games category show just the Public player count.
Any previously cached player count is not invalidated, and the Total Public + Private count for some worlds is now displayed alongside just the Public count for other worlds in all the world lists.
This means that worlds that appear in the front page of the popular category often times get their Total Public + Private count cached before the user clicks on the Games tab. This leaves other worlds looking like they have nobody in them by comparison.
The end result is an even heavier bias that favors user attention towards the very most popular worlds when browsing the Games category, since the difference can be orders of magnitude.