The always enjoyable Virginia Heffernan wrote a column this week on how hashtags are changing the conversations on Twitter.

Hashtags are those little keywords prepended with a pound sign – like in this blog post’s title.

They are the subjective, descriptive little tags added by the tweeter as a way to signify what the tweet is about. Think of them like when you tag a photo on Facebook with a person’s name. You’re adding an additional level of searchability to your postings or tweets.

I commonly see handwritten signs at events where the organizers declare the hashtags for their event. This lets everyone attending cluster their comments around what’s happening, and gives the organizers an easy way to monitor the conversations about them.

I’ve even begun writing my name tag as @geofftucker at these events so people can follow me. It still seems to be a subtle, in-the-know thing but people are catching on.

Make a habit of hashtags in all your posts. And hunt down who or what you need using them.

“What IS Twitter?”

“I’m on LinkedIn but I don’t really use it.”

“My son/daughter is on Facebook.” (Implied: “But I’m not.”)

Tonight, I encountered Jobfeedr.com.

What’s Twitter good for then? This is what it’s great for: direct feeds of job postings for select cities (of COURSE Seattle is included) and professions of interest. Straight to you, via your computer or your phone.

Visit it, play with it, and subscribe to the feed relevant to your job search. It’s a straight pipeline, real-time, of job postings as these savvy recruiters post them.

Decide post by post whether to apply rather than  surfing job boards – that drecky old way of finding a job.

As my blog shows, I’ve been reading a lot about social media as it relates to job search. It’s the latest, greatest way gaining adoption as Monster.com and CareerBuilder.com fade.

Why the fade? One, they’re no longer the new kid on the block. Two, new technologies are sexier, quicker, better refined. Last, audiences are distinctly more self-selecting than 10 years ago. Just as television fragmented into cable, aggregate sites like job boards are now fragmenting into niche services.

Technology will continue to accelerate everything. And “change” is the game in 2009. Embrace it, run with it, and make it yours.