I did this with my Arcadia project (about 5 years ago now) and it did not work really, for many reasons. First off, life interceded with lots of personal junk happening that sparked delays.
http://www.mindtoygames.com/arcproject.htmlMost of all, I agreed that doing this ceded some control over the game design to people with a paying interest, not always very balanced in terms of making the best, cohesive game possible.
I did it mainly because at the time, I really felt it was a bold experiment in getting the best possible looking and sounding game to the players without breaking my own bank. I got coverage with various game sites, etc. but also sales were not great really: I only got 42 total sales at $12.95 ($7 off the proposed full price), and it wasn't enough to fund the game really.
I'd say tread carefully if you choose this route of making a game. A large fanbase is necessary, along with lots of discipline to stay on course.