I don't know if it's particular to my city (Boston), but when I've worked with recruiters they've almost always led to interviews and offers. They have a good handle on what the hiring companies are looking for and how to position candidates to at least get a foot in the door. They're also annoyingly persistent and can dig into companies and bug the hiring manager directly, going around HR, which yields better results most of the time.

I wouldn't be so dismissive of recruiter spam, if you're really looking for responses back from companies.