The 6 friend photos that Facebook chooses for the smaller friends list box across the top banner at the top of the new Facebook Timeline profile are much more likely to show friends who are more likely to be your closer friends (and/or Facebook stalkers, crushes, or recently interacted with friends). The 6 friends photos that Facebook selects as your large profile picture selection box are selected at random. There is no specific pattern or strategy to how Facebook decides which photos to use for each user.
In addition to selecting a small and large photo for each user, Facebook also uses the photos that you select as your cover photo to create a unique photo collage for each user. Your cover photo can only be one side of a photo; it cannot be a split image where one part of the photo is visible over another. For example, if you had a photo of yourself with some friends and wanted to use part of that photo as your cover photo, you could not pick the center portion of the photo because there would be two sides of a single image instead of one.
Users can choose to make some of their other photos invisible by clicking the eye icon next to them.
The little six-photo friend image box appears to indicate friends Facebook has determined to be some of your closest friends and/or those most interested in you, based on their "facebook" interactions with you (and/or your interactions with them or each other).
It's possible to add more friends by clicking the "x" next to their image but it may not change what information Facebook has about them. To delete a friend, simply hover over their photo and click the "x" icon that appears.
The little blue dot next to some people's names indicates they have posted something on your wall. Clicking on their name will take you to their profile page.
The green check mark indicates that you have accepted a request from them to become friends. Once you accept, the two of you can talk at will.
The red circle with a white X through it indicates that someone has sent you a private message. You can read these messages by clicking on the small envelope icon next to your inbox title.
The large blue number next to some people's names is their "fan" count. This is different than your own fan count - your own fan count is shown as a small blue dot next to your name. The more fans someone has, the higher quality of life they are able to lead!
Facebook most certainly takes into consideration who views your friends' profiles (and images) and who views your friends' profiles (and photos). If there's a pattern, Facebook will use that information to show you which of your friends might have been interested in someone else last year, or this year.
For example, if you have a lot of old high school classmates on your list and many of them live in different states or countries, then Facebook will use that knowledge to show you a "top 10" list of their former classmates who were shown on your News Feed at some point in time. Even if they didn't like any of those individuals, Facebook assumes that you probably know someone else that they liked so it shows them to keep the relationship flowing.
If no one you're connected to has recently checked out your friends' profiles, however, then don't worry about it. There's no need to contact anyone unless you want to.
Facebook determines those nine friends based on several factors, including your interactions with those people on Facebook, profile views, tagged photos, wall posts, likes, comments, viewed photos, private messages, mutual interactions, friends who are currently online, friends you've added to the "close friends" group, and friends you've added to the "close friends" group. The more interaction you have with someone, the more chances there is of you being matched with them.
There are also other ways to find friends on Facebook, such as through people you know or via Facebook searches. However, these methods may not be as effective as matching with existing friends.
When you first sign up for Facebook, it takes a while before it begins matching you with friends. This is called the "friend discovery period." During this time, it's possible that you won't be able to see some friends in the list. They might be outside of the network where you work or go to school, for example. There's no need to worry about missing out on opportunities to connect with people because of the discovery period - it only lasts for a few days!
After the discovery period is over, your friend list will be full of candidates. Use your judgment when deciding which ones to add and which to leave alone. Some people may even want to be left alone so they can keep their privacy intact. If you come across someone who doesn't appear to be a match, just move on to others in your list.
According to Motherboard, Facebook determines those nine friends based on 12 factors, including your Facebook interactions with those people, profile views, tagged photos, wall posts, likes, comments, viewed photos, private messages, mutual interactions, friends who are currently online, friends you've added to the "close friends" group, and group membership.
They may show high on your friends' list if you both often check each other's profiles. Post comments, likes, wall postings, tags, and other forms of interaction are all examples of interactions. The more interactions they have, the more likely they are to be at the top of your list.
Mutual Friends: These are persons with whom you and your Facebook buddy frequently engage. Your most recent friends may be at the top of your friend list simply because that was your most recent Facebook activity. However, people also show up on your friend list who wouldn't necessarily fall under this category - for example, your contact list might contain names of people who don't interact with you on Facebook but who you still want to keep track of.
Online Friends: This is a new feature introduced in Version 4.5 of Facebook software. Any person who has an online presence (i.e., a web page) can become your online friend by submitting their information. Once they submit it, they will appear on your online friend list even if you haven't spoken with them via Facebook's messaging system.
People You May Know: This is another new feature introduced in Version 4.5 of Facebook software. If someone appears on your friend list under this category, that means they have submitted their email address or phone number and provided it to you through Facebook. They can then send you messages directly from your friend list.
Their profiles will include an arrow icon next to their name indicating that they have approved your request.