Canon has followed the lead of other lens manufacturers by offering lens caps, in different sizes, that are much easier to use when a lens hood is in place. These ‘center pinch’ style lens caps are much easier to use because the catch mechanism is in the center of the cap, making it easier to reach into the lens hood when the lens hood is in place and on the lens. This is awesome. Here are some links below if you are interested in picking some up.
Canon lens caps at B&H: