There have been lots of examples of online backlashes recently. For instance Motrin.
Neville Hobson has a really comprehensive round-up of why it’s not good to agree to supply a major online conference with internet access which then results in an epic fail.
The only thing I’d change is that the warning came at the very first moment they had a problem supplying LeWeb08, and they should have been publicly reacting from the moment it happened. It’s already four days after the event, and attempting to defend yourself by saying a major convention for online professionals and geeks is demanding on internet resources is a bit like saying that you were surprised when you put your hand in a fire and it was really hot.
If you’ve got 1600 influential online professionals in one place it’s A: the time to really shine no matter what the budget, and B: the time to have a backup policy in place, and some emergnecy planning.
Because no matter who is actually correct, or what the actual amount of service was, the chance to impress that many people in the current economic climate is pretty rare.
Contract it with the recent shining social media reputation management example from Ford.
Funnily enough, Neville has an interview with Scott Monty, who stopped the PR disaster.