It seems that you haven't used the new profile pictures feature yet. I have attached a screen shot of where you can access it.
In the "My stuff" menu, click on the "My Profile" link. you will then be taken to your profile. While viewing your profile, on the top left, there should be a yellow box outlined with a orange border with a link inside of it ("Upload Profile Picture"). Click on this link to add a new profile picture. You can have up to ten profile pictures at a time.
Let me know if you still have any problems or if I misunderstood.