The Quick Contacts part of Gmail offers two qualities:
- it shows which contacts that also have Gmail are online and available for chat;
- by clicking on the name, Gmail composes a ready to write message to that person.
By default the Quick Contacts part shows other Gmail users in your contact list first. Most frequently used contacts are presented first. Non Gmail users appear after them, even if they are your most frequently used contacts. If you have many contacts, some will not appear at all. Life sometimes hurts!
There is a solution: change the default settings. Go to the Contacts list. On the right side of all contacts you will see 'Auto':
- change 'Auto' to 'Never' if you don't want certain Gmail users to appear in the Quick Contacts part;
- change 'Auto' to 'Always' if you want certain non Gmail users to appear in the Quick Contacts part.