I don't think it was a shock that Tony Sparano was fired, they didn't want him for the start of the season, they wanted to fire him during the season, but then the Dolphins rattled off that streak, so after a tough loss to Philly this was a perfect time to strike and get rid of him.
As for Todd Haley, it's tough. He wasn't a good coach for sure, but in his defense he lost Matt Cassel, Jamaal Charles and Eric Berry so there is an excuse. 19-27 is his final record and old friend Romeo Crennel is taking over as an interim coach. There were also reports that GM Scott Pioli and Todd Haley didn't see eye to eye a lot and was part of the cause for termination.
A lot of people are upset at the timing of the deal, but I think it's fine. I like this time as a trial period and also it gives them time to get a Bill Cowher and Jon Gruden out of retirement.