It is definitely the ME contact. See this page and it describes that icon (showing it as John, the owner of the phone), and how it is used to access "guest" mode when lending the phone out. You will always appear Blue, guests will appear White. Why it's there is the question.
It may be that it's waiting for you to update your ME contact. That would be done in People. Go to the People app in your App Tray, then click on "All Contacts" at the top. The first one you'll see is "ME. That is the one you need to edit.
When I do what is explained in the video, it pulls up the ME contact information from the contacts. It never offers me a guest mode selection.
Not sure it is a big deal, since I would never let anyone use my phone that I didn't trust.