I don't have too much to say, but it sounds like a good idea.
Showing a company that "25 BTC have been pledged to you, if you begin to accept bitcoin!" or something like that might be compelling for them to begin accepting it.
As a slight twist, I think the big companies should be petitioned, but you're right that Bitcoin will probably be accepted by the little guy largely before the big guy.
I am willing to bet several companies will find themselves risking obsolescence by Bitcoin-based start-ups before they accept it