That's Joanna Hoffman, who was also part of the Macintosh team. The Isaacson bio shares an anecdote about how the Mac team would annually give out an award to the team member who had proven most able to stand up to Jobs, and Hoffman won it the first two years. It was fun to see an example of why.
Another figure is (if i'm not mistaken) Mac UI & Icon designer Susan Kare whom stands next to Paul Rand. She has a distinct smile. She seems a bit quite enthusiastic being next to a legendary designer. I bet she is the only one, other than Jobs, who knows the importance of the visitor.
