Sellers: Please DO NOT cancel any services until your agent calls you to let you know the closing has been "recorded" (meaning, the closing attorney has recorded the deed at the county register of deeds office and your proceeds can be released). Otherwise, if there were to be any unforeseen delays in recordation your property could be uninsured or utility services not working.
Buyers: You are responsible for contacting utility and service providers before closing to establish or transfer services. Some providers (such as water/sewer) may require a signed "Closing Disclosure" or "HUD" statement, which should be available at closing from the closing attorney.