Boring and overrated

I don't get the fuss with this movie. Very good acting from the central characters aside, what makes it so special?

It was uninvolving, without any real sense of danger or tension, until the moment the two bank robbers got into their getaway vehicle. Most of the goings on outside the bank were cheesy and over-dramatic. How accurate was it to the real events it was based on?

None of the characters were particularly likable and that goes for the members of the public too. I cared nothing for the hostages, and how could you when they were treating the situation like a party atmosphere? Maybe that's a realistic portrayal of the people that were involved but where exactly does it leave you when you can't feel anything for the characters?