I was at Seaworld Orlando the same day and nearly the same time this happened and there was this fairly large guy sitting next to me on Kraken and they had to get 4 guys just pull the shoulder restraints over him and strap the seat belt in. When we where on the first hill that would set the lift up his shoulder restraints came off. Keep in mind the hill that set the lift up is only like a 3ft drop then it goes strait to a chain lift 175 feet in the air. After that they had to reverse all the trains and reset the whole ride eventually they got everything back in working order though... After that they told the guy is over the weight limit to ride the ride.
The only reason the woman died was because she was over the weight limit and the restraints couldn't hold her weight. I've been riding Roller Coasters since I was about 6 and never had a problem with the actually coaster... Your more likely to die from a vending machine than a coaster.
And may the lady

and all my condolences go out to her family.
EDIT:
Originally posted by RuthHavoc
Meh, I prefer getting shot at and watching out for IEDs compared to riding roller coasters. :fa:
You have a one in 300 million chance of dying from a roller coaster.. There nothing to be afraid of :p