The exclamation light would be your brake warning light which could mean your emergency brake is on, or you are low on brake fluid either from worn brake pads or a leak in the system.
(Editor's note: The Tire Pressure Warning System light also has an exclamation point, so it could be that as well. Here are pictures for both lights:
Tire pressure: http://carpoolwithbill.com/wp-content/uploads/2010/08/tpms_display1.jpg?w=300
Brakes: http://www.carservicetips.com.au/wp-content/uploads/2009/07/brake3.jpg (Sometimes the word "brake" is not present))
Happy, safe driving!
〉 Answered on Jul 5th, 2012 by Colleen McGee, Driving Instructor at Americas Driving School
Usually this means it has something to do with your traction control OR low tire pressure. I would check with your manual to make certain. Different manufacturers sometimes mean different things. Thanks
〉 Answered on Jul 5th, 2012 by Deborah Renshaw, NASCAR Professional Driver at Deborah Renshaw Racing
An exclamation point inside or next to a triangle means a problem with tire pressure, probably a low tire. By itself, an exclamation point means one of your guages or sensors is registering a problem, check your manual. It is not an engine check light.
〉 Answered on Jul 5th, 2012 by Jo An Holt, Automotive Journalist at Holt & Associates
Natalie, if that light is coming on, it is warning light for your TPMS or Tire Pressure Monitoring System and it would come on for one of two most likely reasons: low air pressure or a bad/faulting TPMS sensor.