Yahoo! Inc.'s (NASDAQ: YHOO) purchase of corporate email provider Zimbra this week was one of the more exciting pieces of news I've seen from the Sunnyvale, Ca. company in a few years. Yahoo!'s recent spending spree also includes BlueLithium, a maker of online behavioral marketing services. So, with two large acquisitions, is Yahoo! on the way back to stardom as it tries to more fully complete with Google, Inc. (NASDAQ: GOOG)? Perhaps. in any case, the Zimbra buy was very wise for Yahoo!, and by all accounts, the price was a bargain compared to the business potential it could bring Yahoo!

The Zimbra buy will beef up Yahoo!'s email services, of course. One of the bright lights these days for Yahoo! is the immense success it has had with gaining and retaining web-based email customers. More people use Yahoo! email than any other email service on the planet, and it handily beats Microsoft Corp.'s (NASDAQ: MSFT) Hotmail as well as Google's Gmail. I still find Gmail to best web-based email out there, but it was not there first, having come more than seven years after Yahoo!'s mail arrived on the scene. As usual, first-movers get all the glory -- and users -- which explains why Yahoo! is still at the top (by far) and why online auctioneers have failed to catch up with global online auction leader eBay, Inc. (NASDAQ: EBAY).

Yahoo! has wisely spent $350 million here, as it will inherit a very robust base of business email clients that it can either fold into a new global email system that is used by customers and businesses, or it can get innovative in the business space and fight with Microsoft's Exchange email system for businesses as well as fight off Google's slow-but-sure entrance into the same market. After all, email has been Yahoo!'s greatest success, but whether it remains at the top or allows the competition to eat its lunch won't be known for a while.

As Doug noted yesterday evening, Yahoo!, Inc. (NASDAQ: YHOO) has agreed to purchase behavioral advertising company BlueLithium for $300 million. With Yahoo! being seen by some as an attractive takeover target amid still-unimpressive performance as of late, was this too much for the struggling company to pay for an ad company? You make that call. My call is that Yahoo! is desperately seeking something to convert all those eyeballs across its web network into dollars. A lot of dollars.

BlueLithium is a company that deals with consumer psychology and extremely targeted marketing, and that's just what Yahoo! needs to more fruitfully compete with the likes of Google, Inc. (NASDAQ: GOOG) and Microsoft Corp. (NASDAQ: MSFT), now that the latter has closed the $5 billion+ deal with ad firm aQuantive. Are the 'big three' trying to consolidate the internet advertising and targeting market? You could say that.

If Yahoo! can leverage BlueLithium's technology that tracks web surfer behavior across multiple websites in order to deliver the most relevant ads possible, then it may have something to celebrate. The whole point of advertising in the internet age is to make the marketing as customizable to each individual surfer as possible in order to convert them, at some point, into a paying customer.

Yahoo! (NASDAQ: YHOO) will acquire ad network and targeting firm BlueLithium for $300 million. The web portal company describes its new division as one of the largest and fastest growing online global ad networks that offers an array of direct response products and capabilities for advertisers and publishers.

In other words, Yahoo! has purchased another company to expand its network of partner web sites. CEO Jerry Yang put it this way: "This acquisition will extend our ability to deliver powerful data analytics, advanced targeting and innovative media buying strategies to our customers, who are increasingly looking for these insights. By leveraging BlueLithium's complementary expertise and tools, we will be able to better address the needs of our performance-based display advertisers and enhance the value of our publishers' inventory."

The BlueLithium network covers 145 million unique visitors each month.

What this means is that Yahoo! is getting deeper into the display advertising business, hoping that targeting software can begin to reverse the slide of dollars that are moving to search-related ads. It is probably not a good idea. At this point Microsoft (NASDAQ: MSFT) and AOL have entered similar businesses, and it is unclear how this will help them ramp up online ad growth rates beyond the 10% to 20% where they stand now.

Investors would be silly to get overly excited.

Douglas A. McIntyre is a partner at 24/7 Wall St.