Oprah does it. William Shatner does it. Even the President Twitters. One better, Martha Stewart and Snoop Dog not only Twitter; they Twitter each other.

Everyone seems to be all atwitter about Twitter these days. But is it really the online jugernaut to be, as it seems?

Not so fast...

Yes, we know that Twitter had 7 million unique visitors in February of this year.

But, here is some wet blanket news from Nielson's online arm that measures Twitter's traffic (say that three times fast).

According to Nielson, 60% of all new Twitter subscribers drop out after 30 days. Ouch!

Just to give you a little perspective; Facebook loses about 30%.

Twitter doesn't release for public its number of subscribers. But, let's do the math. They may be growing their subscriber base anyway, for now, despite losing more than half of each new signups a month later. Eventually, however, the number of potential new subscribers just won't be there.

Then what?

Will microblogging do a slow fade?

Can you say information overload?