Since the image doesn't jump around, they don't appear to twinkle. There's always an exception though. In very turbulent air, even planets can appear to twinkle. This effect also plays with a star's color. Blue and green light get bent more than orange and red, so sometimes in very turbulent seeing a star's colors will rapidly change.
Twinkling is actually a serious problem for astronomers.
Next week's Snack will deal with how it affects astronomers and what they do about it.