See this snapshot:Which friends' come under the More Online Friends List?Okay, now many of my friends are offline; why is it that some of them appear in the main list (as offline) while others do not.I see many friends I never interact with on my Main List and a few I recently chatted with on facebook in my More Online Friends List.What's the algorithm behind this sorting and categorization?
On what basis Facebook Categorizes the online friends' list?
facebook;facebook chat
I believe that the Main section are friends you have put into a specific list. The More Online Friends are friends who are not placed into lists.The lag in online/offline inaccuracy is due to the refresh rate set by Facebook.Facebook is HUGE. They have a refresh/cache for the online/offline of users. Different areas most likely have different cache/refresh times.