There is a new article "Costa Concordia: the inside story of the night of Friday, January 13" which has some interesting information.

While I have yet to see a complete, concise timeline, it would appear that things went bad very fast. The initial damage seems to have occured at about 9:40 pm. According to the Telegraph article above, people felt a strong impact, and the lights went out quickly.

The Third Officer was in his cabin, and when he opened his door there was already water in the passageway. He went immediately to the engine room, which was already beginning to flood. “Within 15 minutes, the engine room told the bridge that there was nothing to be done,” he said. “The situation was beyond repair.” By 9:45 pm the ship had a 7 degree list.

Assuming this is a reasonably accurate timeline, the delays by the captain in calling for assistance, telling people all was well, and giving the abandon ship order is unfathomable.

One also wonders why the ships watertight bulkheads didn't seem to slow the flooding, or control it entirely. The hull damage visible in the phots that have been published, while severe, does not seem to have gone the length of the ship. I would speculate that either there is more hull damage than has been visible, or some or all of the bulkhead hatches were never closed.