Apparently the rules say there has to be a drill within the first 24 hours. In this cruise, it was scheduled for the next day; the ship had left port earlier on Friday, so for many passengers this wreck happened on their first night on board. So, a bit of unlucky timing there.

There's an article about the tradition on The Guardian.

Accident happened at 9:40pm. Abandon ship given at 10:50. At 2:30am, there were 300 people left. So around 4 hours.

It sounds like a long time to me, especially compared with the 90 seconds allowed to evacuate a jumbo jet, but apparently its normal to take many hours. It took a couple of hours to evacuate the World Trade Centres, and I've read of other cruise ships also taking hours. Obviously conditions here were not ideal; the ship listing meant that half the lifeboats couldn't be used. On the other hand, the ship being in shallow water meant it didn't disappear under.

Early reports implied that the power cut caused the crash rather than vice versa. I am not yet clear who knew what when. The passengers were suspicious very early, and happened to be right, but that doesn't mean much. The crew who reassured them may not have known any better. Did the captain know immediately that the ship was holed?

Although it looks bad for him, the way the company hung him out to dry so quickly, was disconcerting. There's a lot of PR, manoeuvring over possible law-suits, and trial-by-media going on.