Google announced today that you can now star individual contacts in your Google Contacts list, just as you can star important emails. Seems like an easy way to quickly identify and find the people who you message the most.
Contacts you star will be put in a new "Starred" group. If you're using Android, contacts you star on the desktop will sync with your Android Favorites group.
This feature is still rolling out, so you might not see it just yet. When you do see it, marking a contact as a VIP will be as easy as starring them in your contacts list.