If you're wondering why the term "attention" has suddenly replaced "eyeballs" and "stickiness" as the new media buzzword du jour, look no further than Seth Goldstein.

A former entrepreneur-in-residence for Flatiron Partners, where he built and managed a $75 million new-technology investment portfolio, Goldstein admits to plugging the term shamelessly to friends and colleagues, after first stumbling onto it two years ago.

"I was working with Josh Schachter in 2004 and heard him summarize what a tag was," says Goldstein, refering to the human-applied word label used to sort Internet content on Schachter's site, del.icio.us. "He said a tag is just crystallized attention, and it stuck with me."

Two years later, that introduction has resulted in Goldstein's participation in the launch of at least two early-stage companies: the non-profit Attention Trust and for-profit Root Markets, two outfits dedicated to helping users and marketers quantify attention as yet another metric of Internet use. It's also resulted in a string of invited appearances at industry gatherings such as the O'Reilly Emerging Technology Conference and the Release 1.0 PC Forum.

While not the only person touting "attention" as a new way of looking at the Internet publishing model, Goldstein takes credit for "galvanizing thought" around the concept on the business side of the Internet community.

"My wife, who works for AOL, is my biggest critic," he says. "A year ago when I was cooking up Attention Trust and talking about helping users take control of their own attention data, she was, like, 'No one cares,' but I kept doing my thing. A year later, she gets an e-mail from a senior executive from AOL saying, 'We need to get our arms around not only Web 2.0 but also attention. Have you checked out Attention Trust?'"

Goldstein chalks up the sudden acceptance to a number of factors. First and foremost is the growing realization that business sustainability on the Web has become less an issue of quantity than quality. Attract the so-called "alpha" users who can drive development, propel your message, and add inbound HTML links to raise your site's PageRank, and the Internet trade winds will take even the smallest company wherever it needs to go. Fail to do all those things, however, and you'll find yourself spending millions just to escape the Internet equivalent of the horse latitudes.

Like most ready buzzwords, "attention" means different things to different users. For Internet marketers, a group in which Goldstein claims early membership, it means intelligent lead-generation -- knowing who views what and for how long. Dubbing lead-generation the "waste management" side of new media, Goldstein said he cofounded Attention Trust as a way to help educate Internet users about just how much information they were casually throwing away, and to set up a possible marketplace so that alpha users could get more value in return.

"The dirty little secret of the Internet is that most of the content you see each day costs nothing, because you pay for it in other ways," says Goldstein. "You pay for it by supplying additional pieces of information about yourself to advertisers every time you click on a page or add a new link."