According to the Scott County Election Summary Report, it was 60.91% voting for No, and 39.09% voting Yes. The voters have spoken, and they didn't like the Promise.
In my opinion, a big part of this had to do with how the process was handled. Despite taking over a year, every detail wasn't hammered our. Special elections always rub people the wrong way, and this one was no exception. The commissioned UpJohn study was a piece of junk, which gave for more ammunition to the against side than the pro side. The pro-Promise side didn't do a good enough job of explaining how the concept would work, as evidenced by commenters on the QCTimes website that still didn't understand the concept as late as YESTERDAY.
Even if everything had been done perfectly, its impossible to say if this issue would have passed. One thing I do hope, is that it forces city leaders to reconsider the idea of special elections being a good way to pass things that they worry wouldn't fly during a general election.