On Wednesday's edition of Investor Beat, host Alison Southwick and Motley Fool analysts Taylor Muckerman and Jason Moser take investors through the biggest stories from the market today.

When Mary Barra replaces Dan Akerson as CEO of General Motors (GM -0.32%), she'll make the history books as the first female head of a U.S. automaker. In the lead story from today's Investor Beat, Jason and Taylor talk about the challenges ahead for Barra and discuss the year's best shake-ups in the corner office.