There are some issues with the design of the current contact list. Specifically:

 * The use of non-standard text sizes creates breaks a11y and looks a little odd
 * The placement of the name isn't vertically centre-aligned - this doesn't look great in most cases, and makes the list harder to read
 * The contact images are a bit big

Some fixes for this:

 * Use standard text sizes
 * Set the contact images to 48x48px
 * Don't show chat status in the list and vertically center the avatar names
 * Use separators between each row in the list

Mockup: https://raw.github.com/gnome-design-team/gnome-mockups/master/contacts/png/selection.png