According to internal numbers, WSJ.com hosted 15 million unique visitors in March, a 175 percent increase over March 2007, says Alan Murray, executive editor of the Wall Street Journal Online. Page views came in at around 165 million, up 75 percent year-over-year.

"I don't know of any news site that's growing at that speed," he says. "I don't think this has gotten much attention."

As is common, Nielsen Netratings came up with a somewhat different set of measurements. Nielsen's March numbers aren't out yet, but it reported 6 million uniques visiting WSJ.com in February of this year, versus 3.4 million in the year-ago period.

"You don't want to tie yourself too specifically to any one number, but the trend is clear, says Murray. "We are rapidly growing our readership."

Murray says there's no one "silver bullet" the site has used to build traffic. "I think maybe it's a silver shotgun shell -- there's a lot of buckshot."

Among the most significant was the decision by Journal managing editor Marcus Brauchli to create a unified news desk for print and online.

"That had two really important effects," says Murray. "First, it got the entire news operation thinking on a more systematic basis about the online edition. Second, it really freed up my team to focus on making the product better, because we weren't managing the daily news flow anymore."

Incidentally, the joint news desk was created last summer, well before News Corp. took control of Dow Jones.

"A lot of this stuff precedes Rupert Murdoch, but Mr. Murdoch has clearly supercharged all the trends," says Murray.

Other developments on the content side include a significantly -- although gradually -- redesigned homepage that "surfaces" stories more efficiently, and greatly expanded offerings in areas where, unlike in business news, the Journal welcomes non-subscribers: politics, travel, sports, food. (It also made all of its opinion content free in January.)

On the technology side, he says, "We've gotten much smarter about search engine optimization, and much smarter about working with portals and aggregators. We've just gotten much closer to best practices."

Of course, through those aggregators, like Google News, it's often possible to access stories for free that would otherwise only be available to subscribers. One tech writer even showed how it was possible to read the entire Journal online without ever paying a penny.

"If somebody really wanted to spend their whole day doing it you might be able to reconstruct the whole Wall Street Journal, but why would you do that?" says Murray.

He notes the paper's subscriber base of over 1 million is still growing at a rate of around 10 percent annually.

"I think this is really what Mr. Murdoch acknowledged in his comments in Davos," he adds. "They're really two different audiences and they're looking for two different things and it's possible to serve both areas."