Poor Yahoo! (YHOO). The company just can’t seem to do anything right in the eyes of Wall Street. Rival Google (GOOG) plunks $3.1 billion for online ad placement company DoubleClick and many analysts waxed rhapsodic about how Google outgunned Yahoo yet again.

Now, Yahoo goes out and makes a $680 million deal for an online ad exchange Right Media on Monday that, on the surface, appears more financially prudent than the “GoogClick” purchase, and investors react by selling off Yahoo stock and pushing Google’s shares higher. Yahoo fell 1 percent in early morning trading Monday while Google’s stock was up slightly. Google’s stock fell into negative territory later in the day though.

Well, even though $680 million is less than $3.1 billion, some still might be wondering if Yahoo is overpaying for Right Media. That’s because Yahoo announced in October that it was the lead investor in a $45 million round of financing for the company. It was later disclosed that Yahoo bought a 20 percent stake in Right Media for $40 million. Based on that valuation, Right Media should be worth just $200 million. But Yahoo agreed to pay more than three times that for 80 percent of the company. 

One analyst speculated that because of Google’s deal for DoubleClick, Yahoo may have felt a sense of urgency to buy Right Media and perhaps overpaid.

“While no financial details were provided on this transaction outside of price, we find the total consideration expensive considering that Yahoo!’s purchase price implies a total value for Right Media of $850M up from $200M a year ago,” wrote Jefferies & Co. Internet analyst Youssef Squali in a report Monday.  ”We believe the timing of it and valuation were greatly influenced by Google’s recent acquisition of DoubleClick.” He added that the deal makes strategic sense but will hurt earnings in the short-term.

Yahoo, to its credit, is making many aggressive moves to stay competitive with Google. Yahoo is often criticized for not being a voracious acquirer while the truth of the matter is that Yahoo makes many deals; it’s just that Yahoo hasn’t landed the big fish that Google has with DoubleClick and last year’s $1.7 billion deal for YouTube or that News Corp. (NWS) did with MySpace parent Intermix Media back in 2005.

But the Right Media purchase is a smart one for Yahoo. Venture capitalist Fred Wilson of Union Square Ventures raved about the deal in his blog Monday morning. 

Right Media should compliment Yahoo’s new search platform, Project Panama, which has gotten praise so far for leading to more relevant search results on Yahoo, has not led to increased revenue and profits for Yahoo just yet. Plus, Right Media already has a successful online ad exchange running. DoubleClick, on the other hand, just announced earlier in April that it is starting its own ad exchange. So with this deal, Yahoo appears to have gotten an upper hand on Google in the ad exchange business.

During a conference call with analysts Monday morning, Yahoo chairman and CEO Terry Semel said the deal would create an “open, accessible and vibrant” marketplace for advertisers and publishers and stressed that this would be something that differentiates Yahoo from its competitors. Without mentioning Google by name, it appeared that Semel was taking a jab at Yahoo’s largest rival.

Susan Decker, Yahoo’s acting chief financial officer and also the head of a division that oversees relationships with Yahoo’s advertising customers, added during the call that Right Media’s revenue in 2007 should double from last year and that the company, on a standalone basis, is on track to break even this year. She also said that Right Media should add to Yahoo’s free cash flow within twelve months  of the deal’s closing, which is scheduled to take place during the second or third quarter of this year. 

Still, investors appear to be hungering for even bigger developments from Yahoo. The stock surged 26 percent this year before the company’s first quarter earnings report due to optimism about Panama. But Yahoo missed first-quarter forecasts and issued tepid guidance for the second quarter. Since then, the stock has fallen 12 percent as investors realized that it will take some time for Panama to significantly boost Yahoo’s results.

With that in mind, rumors about the possibility of Semel stepping down have once again begun to resurface. On Friday morning, Yahoo’s stock briefly popped due to a blurb on Theflyonthewall.com, a subscription surface that reports Wall Street news and gossip, that mentioned increased chatter about Semel leaving Yahoo.

A company spokesperson shot down the rumors, however. “Terry Semel has no plans to leave the company and is more energized than ever about the future,” the company spokesperson said in an e-mail to me late Friday night.

Still, investors have to be wondering what, if anything, it will take for Yahoo to gain back some of the market share in search that it has lost to Google.

“This deal wasn’t very surprising,” said Scott Kessler, an equity analyst with Standard & Poor’s. “The only thing that was moderately surprising was the timing and the price. People may say they should have done this last year when they could have gotten it for a lower price.”

Some shareholders might also be disappointed by the fact that even though Google spends virtually nothing on advertising and marketing, Yahoo announced Monday that it is launching yet another multi-million dollar marketing campaign.

The company is planning on spending heavily to promote new services like Yahoo! Answers and Yahoo! oneSearch, a version of Yahoo search for mobile phones.  The marketing campaign kicks off Monday with radio and TV spots and the theme of the ads, “Be a Better…”, are meant to show how you, Joe and Jane Q. Nethead, can make better decisions by using Yahoo.   

But based on the reaction to the Right Media deal Monday, it looks like Wall Street wants Yahoo to emulate its own marketing hype and Be a Better Creator of Shareholder Value.