Updated from 2:10 p.m. EDT

DoubleClick

(DCLK)

, the online advertising firm, unveiled a deal Tuesday that would strengthen its position in the email marketing realm and potentially provide ammunition against critics who question its commitment to protecting online privacy.

DoubleClick announced that, for stock valued at $191 million, it would acquire

NetCreations

,

(NTCR)

which gives its direct marketing clients access to 15 million email addresses and is adding an estimated 50,000 names to its database each day.

DoubleClick went out of its way to emphasize a couple of facts about NetCreations. First, the firm noted that NetCreations allows its customers, from

Dell Computer

(DELL) - Get Report

to clothing retailer

J.Crew

, to send targeted emails only to Internet users who are willing to receive messages on certain topics.

In the midst of a growing debate over Internet privacy, the acquisition could be a significant one for DoubleClick, which is based in New York. David Doft, an analyst at

ING Barings

, said he recalled listening to Rosalind Resnick, Net Creations' chairman and chief executive, preaching about privacy years ago at direct marketing trade shows.

"It's something that from a public relations perspective is definitely a positive for DoubleClick," said Doft, who rates the company's stock a buy and whose firm has not done any underwriting for the company. "From a privacy standpoint, NetCreations has been at the forefront long before other companies."

Privacy Issues: a Hotly-Debated Topic

DoubleClick stoked a heated discussion over online privacy last year after saying that it intended to merge anonymous data it collects online with a database on catalog shopping habits put together by an acquired company,

Abacus Direct

.

But with pressure coming from the government and privacy advocates, DoubleClick later postponed that strategy and is moving ahead more cautiously with designs to take advantage of the Abacus data, analysts said.

DoubleClick, like other similar companies, tracks Web users browsing habits, getting anonymous information for clients, typically without gaining consent. The acquisition of NetCreations allows the combined company to fortify its email marketing services, which are emerging as an alternative to Internet banner ads.

But Richard Petersen, who follows DoubleClick for

CS First Boston

, suggested that the privacy issue had largely faded from view on Wall Street, and that despite Resnick's proven track record, NetCreations' "opt-in" strategy would not have a huge positive impact.

"In the minds of investors," Petersen said, "it's an issue that has been fairly well put to rest."

In Internet privacy parlance, an "opt-in" provision compels companies to get permission from Internet users before collecting information about them, but NetCreations' email addresses are obtained on a "double opt-in" basis, meaning marketers must go a step further, confirming consumers' voluntarily participation.

"NetCreations isn't exactly well liked by privacy advocates," although it has made a conscientious bid to address their concerns, said Chris Hansen of

BofA Montgomery

. But the acquisition, he said, "is representative of the extra steps DoubleClick needs to take" to assuage privacy worries as the issue surfaces again.

NetCreations' Appeal

DoubleClick also noted that the firm it is acquiring is profitable, unlike a number of other companies doing business in the volatile Internet world.

Last month, however, NetCreations warned that it would miss its third-quarter earnings target by at least a nickel. Citing a slowdown in dot-com spending, NetCreations said it would post profits between 4 cents and 6 cents a share on revenue between $14 million and $15 million, leading analysts to wonder whether more financial setbacks lurked on the horizon.

Petersen, who rates DoubleClick stock a strong buy, said he was more interested in the price NetCreations charges its customers for access to its email lists. The costs right now are very high, he said, and as the novelty of email marketing wears off, the prices likely will come down, potentially hurting business for those in the industry.

And as Internet companies scale back their spending in an effort to stay financially viable, and email users possibly begin to dodge an increased amount of mail, DoubleClick's bet on email marketing services could prove risky, analysts said.

Still, with the NetCreations agreement, DoubleClick would be able to surpass rivals, like

24/7 Media

(TFSM)

, which until now has led the email marketing realm, analysts said. After acquiring NetCreations, DoubleClick could provide advertisers with a trove of roughly 22 million email addresses.

DoubleClick said it would exchange 0.41 shares of its stock for each NetCreations share. Based on Oct. 2 closing prices, the pact represents a per-share price of $12.15, a 17% premium over NetCreations' 10-day average stock price.

Before issuing its profit warning a month ago, NetCreations traded at more than $20. NetCreations' stock finished Tuesday regular trading down 88 cents, or 8%, at $10.50. DoubleClick's stock was down $3.44, or 12%, at $26.19.

Once they gain regulatory approval, the companies hope to complete the agreement in the fourth quarter of this year.

Despite lingering uncertainty over demand in the Internet advertising realm, DoubleClick maintained that this is a prudent time to expand and pick up NetCreations' email marketing services after a full year of negotiations with the firm, which also is based in New York.

"Internet advertising has been weaker over the last six months," Jeffrey Epstein, executive vice president of DoubleClick, said in a conference call with analysts Tuesday. "But we think email will be a permanent and important part of the overall advertising industry."

For DoubleClick, the acquisition is its second in about a week. DoubleClick announced on Sept. 25 that it would acquire

@plan.inc

(APLN)

, a Stamford, Conn.-based Web market research company, in a cash and stock deal valued at $120 million.