While out of town this weekend I was talking with Shawn Blanc about the new design here. He mentioned that one frustration he has is there is nothing to indicate that he is logged in.
Technically this is not true, the menus change when you are logged in, but practically this is true. I added a bit of welcome text to the header of the site, so if you are logged in you will see that, if you are not, then you will not see the text.
If you hit the link, you should be taken to your profile. If you want to change what displays just follow the link and change the ‘Display Name’ dropdown to what you want to be read. (It populates that drop down from: username, First name, Last name, nickname.)