I've had the experience of a company stepping up, mostly unbidden, to make itself accountable to its customers only a few times in my life. Usually, the company is being forced into the action by a class action lawsuit. Sometimes, it's a whirlwind of controversy that they've been resisting for a long time (e.g., the current Sony rootkit/DRM debacle). More often than should be legal, the company won't deal with its problems until legal action is threatened (anyone ever have problems with DSL billing at the phone company?).
But every so often, a company prides itself on outstanding products AND service. They trust in their customers' intelligence, integrity, and discrimination. They try to do the right thing on that assumption -- think Nordstrom (I had a friend who returned jeans a year after buying them there once), the first years of Lexus (I had a friend who worked in customer service there and told me some amazing stories of how far Lexus would go to keep their customers happy), Apple, Google, USAA (if you're lucky enough to be eligible for their service).
The folks at Six Apart today put themselves, from my humble perspective, solidly in that group. There were problems at the service. They acknowledged those problems to their customers and to the general public a couple of weeks ago. They made a solid commitment (financial and verbal) to never find themselves in that position again. Today, they voluntarily charged themselves across the board for violating trust with their customers. They also gave us discretion in deciding how much pain was appropriate to deal back to the service for the downtime (credit for 0, 15, 30, or 45 days of service, with 15 the default). Kudos for stepping up, folks.