It matches job seekers with employers based on their compatibility. Employers and job seekers find matches based on compatible skills (not just keywords,) salary, geography, etc.
RealMatch seems particularly desirable for employers because, instead of a mountain of applications (mostly ill-suited), RealMatch sends only the best matches.
RealMatch should also be good for job seekers because it empowers you to state what you want and then you receive a list of compatible job openings.
Alas, that's just the theory. I don't know how well it works in practice. Do you?