Former top Yahoo advertising exec David Karnstedt (pictured here), who has been parked at a Silicon Valley venture firm since he left the company, has been named president and CEO of Efficient Frontier.

Interestingly, another former Yahoo (YHOO) exec, Ellen Siminoff, has also been CEO at the Sunnyvale, Calif.-based search engine marketing firm. She is now chairman.

Karnstedt, who was SVP of of Yahoo’s North American sales until last fall, replaces James Beriker.

He has most recently been an executive-in-residence at Redpoint Ventures, an investor in Efficient Frontier.

Here is an interview I did with Karnstedt in 2007, when he was at Yahoo.

And here is the full press release:

Efficient Frontier Names David Karnstedt as President and CEO

Former Redpoint Ventures Executive-in-Residence and Senior Vice President of Yahoo!’s North American Sales Brings Extensive Experience to the Post

Sunnyvale, Calif. – April 2, 2009 – Efficient Frontier, the worldwide leader in Search Engine Marketing (SEM) technology and services, today announced that David Karnstedt has been named President and Chief Executive Officer of the company.

Karnstedt most recently was an Executive-in-Residence at Redpoint Ventures, an investor in Efficient Frontier. Prior to Redpoint, he served as Senior Vice President of Yahoo!’s North American Sales with responsibility for more than $3 billion in revenue. During his tenure at Yahoo!, he successfully led the integration of the Search and Display sales teams into one central unit and helped establish Yahoo! as a recognized leader in both display and search marketing.

“We feel incredibly fortunate to have someone of David’s caliber join Efficient Frontier at this point in the company’s life cycle,” said Ellen Siminoff, Chairwoman of Efficient Frontier’s Board of Directors. “David’s extensive experience in the Internet space – specifically search – will be a huge asset as he leads the company forward.”

Karnstedt’s experience includes several industry firsts. Prior to Yahoo!, David led the Direct Sales team at Overture Services, the company that pioneered the paid search industry and was acquired by Yahoo! in 2003. He also served as Vice President and General Manager of Alta Vista, where he was responsible for the consumer business and helped shape product development and marketing strategies that leveraged the auctions-based search approach. Prior to Alta Vista, David served as Western Advertising Director at Wired Digital where he helped to develop some of the first advertising models on the Web. He is also active in the industry, having served on both the Advertising Council and Interactive Advertising Association’s Boards of Directors.

“As the leading global Search Engine Marketing company, Efficient Frontier has built tremendous assets –
including its technology platform, a global presence and a great team,” said David Karnstedt. “I plan to build on these key assets by expanding the company’s leadership in search, diversifying into complimentary product offerings and increasing its global presence. I am pleased to lead the company into its next phase of growth.”

Karnstedt is replacing James Beriker, who held executive positions at the company since April 2007 and was its President, CEO and a member of the Board of Directors from February 2008 until March 2009. The company’s business expanded significantly while James was CEO. We are appreciative of his efforts and contributions.

And, as BoomTown wrote yesterday, so the war of attrition for Yahoo begins.

Not with a bang, but a whimper. And so much whine, I am considering serving up a nice plate of cheese to all players.

But while the first moves by Microsoft (MSFT), which is seeking to take over Yahoo (YHOO), seem a bit weak, it is likely the more significant bombs will start flying next week.

But not quite yet.

First, came a not-so-subtle insinuation from Microsoft Steve Ballmer that he could take his marbles and go home any time.

He noted yesterday in a speech in Milan (Milan? OK, we’ll go with it) that the software giant is “prepared to move forward alone without Yahoo.”

A show of hands of who actually believes this claim, please, a classic go-fish negotiating ploy? No one? We thought so.

Then, comes the artfully worded Wall Street Journal story today, in which it is revealed that some at Microsoft are skeptical of the deal.

Apparently, Microsofties are worried that the job of merging Yahoo into Microsoft will take precious attention away from, well, them!

Well, that’s been the biggest open secret at Microsoft. Almost anyone you talk to notes that the Yahoo deal is risky, but it would be done no matter what due to Ballmer’s determination to use Yahoo to better hammer at rival Google (GOOG).

“This is Ballmer’s war,” said one Microsoft employee to me recently, who also noted that it is still a good move for Microsoft, despite the slowness of the attack. “I doubt he will surrender.”

Well, BoomTown suggested Microsoft do so back in mid-February in a post, noting that Ballmer might do better to use the $41 billion to buy up every hot start-up in Silicon Valley–Digg, Meebo, Slide and even the hopelessly high-valued Facebook–and still have money left over to buy everyone a tank of gas.

The Journal story also listed previously reported names of possible directors for a proxy slate Microsoft must nominate to replace Yahoo’s current board.

They include, noted the story, “former Nextel Partners Inc. CEO John Chapple, former Grey Global Group Inc. CEO Edward Meyer, Jaynie Studenmund, the former chief operating officer of Overture Services Inc., which was later acquired by Yahoo, and former Adelphia Communications Corp. Chief Financial Officer Vanessa Wittman, according to people familiar with the matter.”

Not to be whiny about it or anything, but with no truly prominent Internet executive or figure among these director possibilities so far, BoomTown would have to say we are profoundly underwhelmed by the list.

Thus, we await more powerful forces.

And that might be sooner than later. Microsoft will announce its earnings this afternoon, which–if they are strong and lift the price of Microsoft stock and, therefore, the Yahoo offer–could be the first big gun to fire in the proxy fight.