US spending on e-mail advertising will grow to $2 billion by 2012 from $1.2 billion in 2007, according to JupiterResearch data presented at MediaPost's E-mail Insider Summit.
JupiterResearch estimated that about one-quarter of e-mail delivered to users' main inboxes is now opt-in.
"There's less junk, but there's still as much email--we're competing with other legitimate marketers," said David Daniels, vice president of JupiterResearch, speaking to the e-mail marketers in the audience.
JupiterResearch asked why recipients stopped subscribing to opt-in e-mails. More than one-half said the content was no longer relevant, and 40% said they were getting too many offers.
It is also getting harder for marketers to figure out which e-mail address to use. Nearly two-thirds of US Internet users have three or more active e-mail addresses, according to a November 2006 Bluestreak-commissioned study conducted by ROI Research.
Still, e-mail is everywhere, which is why it is so attractive to marketers, according to David Hallerman, senior analyst at eMarketer.
"E-mail, compared with other forms of interactive communication tools, is not only ubiquitous but also addictive," Mr. Hallerman said.
According to a November 2006 ROI Research report commissioned by Bluestreak, 90% of US Internet users used e-mail several times a day. No other communication tool comes close.
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