How Fleeting is Tweeting?

The buzz today: Twitter's fleeting.

Nielsen Online says more than 60 percent of the microblog service's users stop tweeting a month after joining - meaning its retention rate is about 40 percent a month. Looking back over a year, the company says retention's been closer to 30 percent, or less.

In a blog post David Martin, Nielsen Online's vice president of primary research, says, "There simply aren't enough new users to make up for defecting ones after a certain point." Facebook and MySpace, by contrast, have retention rates of about 70 percent.

"Twitter has enjoyed a nice ride over the last few months, but it will not be able to sustain its meteoric rise without establishing a higher level of user loyalty," Martin says.

So does this mean Twitter's losing its value as a job-hunting and networking tool? Not necessarily. What's not clear from Nielson is how many finance folks are sticking with Twitter. My thought it we should all keep an eye on our followers. If they suddenly go quiet, you might be able to give your thumbs a rest.