19 cats, I'm sure that the knob on top right above the presser bar is for presser foot presser...
It must be a light. How interesting that they decided to mold that into the body like that.
Jennifer23, I think you're right. Looking closer at it (on a bigger monitor) I can see that the right "arrow" is a little longer. That makes sense.
OldSewnSew - It's an interesting idea, but I don't know how they'd implement it. Besides, the knob on the left looks functional....
amcatanzaro - I agree, it's sharp looking. I think that's why I looked at it a couple of times then spotted the mystery.