DF/Tim is/was already famous in the gaming community beforehand though. This helps. It's a bit like if Paul & Ringo created a Kickstarter project saying they're thinking of making a new Beatles album, and wanting to know if anyone would front them the production costs upfront.
To reiterate:
Up till now, it has basically only been the "unknowns" using Kickstarter, hoping that their product and pitch video are good enough. Some of them have done well, but the Double Fine project has made more than any other project in 24 hours.
This project shows what can happen if an already well-known brand goes with crowd-funding. To me, the craziest part is that they didn't even pitch a specific game, just the genre.
