RecruitingBlogs.com has a bunch of information up on Twitter for Recruiting - and it's for free. I love those guys, but you get what you pay for. Between people complaining that it's worthless, and others giving you technical details about hashtags and twitter search, the elemental issue of human contact is completely ignored.
And like all bad systems, recruiters who don't understand this will find the community routing around them.
2) Referrals: Once you've built a network focused on your industry, you'll become a known quantity for the people you engage. If you tweet correctly, you'll get referrals (most people do it wrong - they're just spamming the site and wondering why that doesn't work).
3) Industry research - Twitter works great as an informal Q-and-A for information. From real time intelligence on your clients, promotions, hires, layoffs, and projects, to asking your network how to answer questions on buzzwords, lingo, and technical matters, Twitter works to give you information quicker, making you more interesting on the phone. Think of it as a giant phone-a-friend from Who Wants To Be A Millionaire.
Of course, the reason most people don't get this is they only want to post jobs and magically have candidates appear. That doesn't work. In fact, the posted jobs have the same problem they do on job boards - it's so easy, that most posts are worthless. Twitter is not a job posting service. If that works for you, count those days as numbered. Anything that easy is going to get overused to the point of being irrelevant.
What is the difference between posting on a job board and posting on Twitter? Very little. It's just garbage in and garbage out. Do you really want to post a job on Twitter and have everyone follow up with you? Didn't we learn our lessons from posting to job boards and getting hundreds of resumes from unqualified candidates? Learn this - identifying a candidate is not the same as recruiting them. If you put little value into your tweets, you're not going to get much value out of it. And the community will route around you.
Social Networking is an easy target these days, and one of the complaints is it's growing so fast you can't keep up. It's a valid argument, and let me explain why. Let's say you follow 500 people on Twitter. There are 7,000,000 people and growing on Twitter. No matter what you think of Twitter, you're getting only a tiny, non-representative portion of the community. Like blogs before it, Twitter is already to big to really understand. Your perspective is going to be shaped by who you spend time with. Thus your statements will be true only for you and some of your followers. You cannot understand the entire matter.
Thus we are left with one simple choice when it comes to Twitter (and all things social media). Does it work for you, or does it not? Does your time online yield a useful result, or does it not? Yes, this means there is no one right way to use Twitter. But there are hundreds of wrongs to use Twitter.
Twitter for business can be boiled down to one simple question.
Are you making money from your actions, and are you making money for other people?
If you can't figure out how to do that, the problem is between the seat and the keyboard.