Gmail has recently introduced another security stepup which notifies the the logged in user to receive notification in case they find your account being accessed from suspicious IP address which is explained below :
To determine when to display this message, our automated system matches the relevant IP address, logged per the Gmail privacy policy, to a broad geographical location. While we don’t have the capability to determine the specific location from which an account is accessed, a login appearing to come from one country and occurring a few hours after a login from another country may trigger an alert.
However it doesn’t seem to be working for IMAP and POP of which I tested for IMAP. Gmail team should include this also and possibly in future we might also see some trusted connection like stuff. Apart from this only displaying alert on web interface might not be just enough and there should be an email sent across so that if I am not logged in, I still can get notified.
