I think the question is how is it administered and who makes decisions about what to prioritize.
That's the tricky part.. I would be happy with any one from the core development team doing it.
Would love to see individual developers have access to a kickstarter like platform where they can make the case for what they want to code, how many resources it will take to fund that coding, and people can both fund it and follow the progress.
It looks like this site is trying it:http://www.bitstarter.co
The donors could always either create a freelance job or donate to a job already created and then the freelancers can bid on those projects.
I'm thinking a lot of people would like to passively contribute to bitcoin, by doing something as simple as opening the bitcoin forum, and clicking a button that says 'donate GPU hashs to the bitcoin development fund', and this would be a way to get their contributions.