Are A.J. McCarron and Katherine Webb engaged?

Alabama Crimson Tide quarterback A.J. McCarron and his girlfriend Katherine Webb posed for a picture last night during an event in New Orleans.  The only significance to this is the caption that Martha Stewart put on it.

Did they get engaged recently and have decided to keep it quiet?  She isn’t wearing a wedding ring, so perhaps Martha was merely mistaken.  Or perhaps Martha just accidentally spilled the beans on their relationship.