How many photographers should be at a wedding?

That's overkill, only celebrities have more than one photog cover their wedding. Most photogs work alone or they bring one assistant, and there's rarely a worry about them missing an important moment. My photog worked alone and he captured our entire ceremony, the groom getting ready beforehand, then formal wedding party photos after the vows, the cocktail hour, dinner, reception, spotlight dances, dessert, etc. He was with us for 6 hours which was more than enough because when he left at 9:30, the only thing that happened after that was guests dancing.