I love the idea and execution of Kickstarter, but I do find myself disappointed that much of its "funding" (at least the high profile stuff) is really just pre-ordering.
Although one can argue that is a benefit. You can 'guess' how many you might sell, this tells you how many you will sell. So its a win in that perspective. If you spent $75K tooling up to make this thing and only sold a hundred, well you'd be putting the rest up on Woot! or something. This takes the risk out of it.
Oh for sure it is better than the guesswork of the old way of market research and relying on unfavorable deals with investors, but when put in the same space as actual investments which entail a level of risk, I have to wonder if the pre-orders will siphon money off the "We need 50k to pay our bills while we do something cool for y'all" projects, which I think are also important. For now it's all relatively small so there probably isn't much cannibalization going on, but I see it as an inevitable concern.
I think that this pre-ordering is an exciting development. In terms of physical goods, it allows the creators to accurately gauge demand and prevent waste. In terms of digital goods, it allows creators to get paid for goods before they are released, which is an excellent adaption to the reality of piracy.