To delete a friend from your Friends List, you’ll need to access your Messages section. Click your Messages icon and click Friends List. Beside each of your friend’s name is a ‘delete’ link. Click this link to delete the friend from your list. Your friend will not be notified that they have been deleted.
Ignoring messages is not possible at this time – we are adding this functionality. Please comment here if you would like to see the ‘ignore’ feature bumped up the list of things to do.