I've always been more afraid of human error than a memory card error and because of this I always shoot weddings with 1 card per camera. Now that I shoot with D800s, the 36mp raw files require a 64gb card per camera. In 8 years I've shot hundreds of weddings and I've never had any sort of card error and I've never lost a file. What about you?
Yesterday I was attacked by one of our Twitter followers for "not caring" about my clients because I shoot with 1 card per camera and "when" I get a card corruption I'll be in serious trouble. I've always been afraid of possibly losing a card if I shot with 10-20 per wedding or running out of memory at a key moment. From my experience, my memory cards have been the most reliable piece of gear that I owned. I've had cameras, flashes, lenses, batteries, pocket wizards, cables, and studio strobes go down at weddings but never a memory card. I had 1 friend that told me years ago that a Lexar CF card he had went down during a commercial shoot and he lost a few images but I think that is the only story I've ever heard of this happening and I have a ton of buddies who are photographers.
So what about you? Have you had a memory card go down? If so were you able to recover the images you had already taken? Let's all find out how common this is by filling out this poll.
If you have had a card fail, I would love to hear your story in the comments below. Make sure you mention the exact make and model of the card. I'm curios to know if some cards are more unreliable than others.