We don't use https, which is the secure login, because you're not transmitting any secure data to us 🙂
But last year, the major web browsers made that the standard and started issuing that warning to sites not using it. So at some point, when we have the time (and I have the money) we'll make the transition to that. It's a complicated process for us because it means we have to change all kinds of data points in the forum, places where it links to an image or other piece of information/content.
But again, you don't have anything to worry about, because you're not transmitting anything secure to us anyway. The only data you send to us is your TMF username and password. And those actually are transmitted securely.