It sounds to hackers like "I've got a great idea, all I need is for some one to do all of the work for me, preferably for free, kthxbai."
The best way to attract a hacker type is to build something insanely cool (or at least make a good start of it) and project a trajectory of much more where that came from. Without that, I don't think any idea is cool enough all by itself. I admit, its kind of a chicken and egg deal but there it is for what its worth.
You could also explain what you bring to the table. Past history is useful.
Think about how you would evaluate a software person - you wouldn't just bring a hacker onboard because he went on news.managersspecial.com and posted that he was looking for a business person, would you? You would want to know a lot more about what they were up to, what they've done; and most importantly, what they can bring to the table. Just having good ideas isn't really a qualifier any more - it's what you've done with them that's important.
Assuming that there is already trust and respect - I would want someone who can bring this to the table:
1. someone who understands a particular market & its needs 100%
2. someone to bounce design/sales/marketing discussions off
3. someone who has social and professional connections that I don't have
4. someone who can cook (because I don't have this skill)
Out of all these 1 & 2 is most important - as hackers don't usually have a good sense for UI and users.
If you find a hacker you want - sell yourself with these points.