Good point. She does look like she is glowing and she definitely is beautiful.
I have thought the same kind of thing. Would imagine it's the role she plays in Law & Order SVU. As a police detective, she is a regular gal, with no time for primping. So, this is perhaps the difference. Who is going to believe the reality if she looks as good as she does in this picture when she's chasing the bad guys?
As for how good she looks here. Well, she DID just have a baby. And I'm guessing she's just very happy. That would make a person glow. Doesn't hurt that she has that perfect chin and throat either. She is just stunning. Even if she went back to all dark/black hair, she'd still look GREAT.