How Twitter can help you find jobs?

I read an article in about.com on how Twitter can help job seekers find jobs because employers are also using Twitter to post job announcements. And we thought Twitter is just fun with out any constructive purpose?

How employers use Twitter?
* Invariably, they have a Twitter on their website's home page requesting visitors to follow them on Twitter.
* Some companies post their openings on Twitter.
* Twitter job search engines like Job shout automatically send Tweets of job postings in their search engine portal for employers and job seekers.
* Job seekers use TwitterJobSearch.com which is a job search engine that searches Twitter for jobs that match the keywords that you enter.
* http://www.jobangels.org/ has a Twitter profile where they have written that it is their philosophy to help one find a job.
*And you know Twellow already, a very popular Twitter search engine and a big one.

From the the ways Twitter is being used, I wonder "What is next?"