Jerome the lobbyist angle is an interesting one but not substantively difference then the situation we have currently. (i.e. it's a wash)
I'm actually not at all worried that interested parties could overfund stories, the concern is reporting bodies being captured by a funding source.
If an interested party consistently overfunds a class of stories, you'll eventually staff up to support that interest, now you're dependent an institutional funding stream, this is how capture happens over and over again in the non-profit world.
In the non-profit world you address those concerns by being a membership organization, which is what folks like http://www.mediacoop.ca/
are trying to do