It's a rather neat feature that basically keeps your car in whatever gear you wish.
Slide the slider towards the M and you get an M appear on your Heads Up Display. Shows up where the E usually is.
Now you are in manual mode, so if you shift the gear selector into 3rd for example your transmission will start off in third and stay in that gear. (Not very economical by any means.)
Also don't try doing that and pull out infront of someone moving quickly since the car will bog down noticeably since it's starting out in a higher gear.
One of the good reasons for using it is if you are on an icy mountain pass and you want to start off in 1st gear and not have the transmission automatically shift into the next gear sending you out of control. You can run that manual in first and scream on the RPM's all day long.
Other than changing the E to an M you can keep it in automatic mode and move down to the 3rd gear on the gear selector. This will put the automatic into sport mode (an S will appear where the M or E is usually) and give you better throttle response (since the tranny is basically already at the kickdown point,) at the sacrifice of fuel economy.
You get all that?
