It is sufficient for the time that the forms are in contact with the surface. When removed, 3-7 days after placement, the cure compound or wet burlap needs to be immediately applied. the top surface needs some cure method even with the forms in place.
If the the weather is "hot weather" and the air is dry, forms are not sufficient since the wood breathes and it will dry out. See ACI 305 Hot Weather Concreting. Otherwise, the forms are sufficient for curing until they are stripped. I imagine that leaving the wood forms up for a while will make them ineffective after they dry out. Check ACI 308, the Guide for Curing Concrete for further recommendations.
