The people who fund (or do not fund) the project make that call. In the end, it's up to the fans to decide if the project is worth their time and money. You guys have listed a few "worst-case" scenarios, people not getting their perks or the product not coming out properly, or the money not being used correctly. But stuff like that has happened before Kickstarter existed. I mean, we've all heard stories about bands getting a label advance on a recording, and blowing most of the money on drugs, booze and women. This shit ain't exactly new. I know people who did that with student loan money.
If you're worried about any of that, I suppose you have to think about what kind of people you're supporting. Indie band whose only business skills involve working a cash register? Full-on electronics company with a few products under their belt already? In this age of super-fast information and social media, it can't be hard to do your homework and decide if it's something you want to contribute to.
I'm pretty sure that shit like this is the way of the future, like it or not. At least, until someone comes up with something better. Or someone fucks up so royally that it ruins it for everyone else.
I'm pretty neutral towards Kickstarter. It's a tool. If I have a project in mind, I look at my options and weigh them. I did a Kickstarter (rather, Indiegogo 'cause I'm a Canucklehead) with that SCYTHIA band, to fund the last $3000 we needed to film that music video. The perks were sent out within a few weeks of us making our goal. The $700 we made on top of the 3k went towards production of the new album. The video is out now (and even if you don't like the song, it's a pretty fuckin good video) and everyone's happy. Worked out for us, I guess.