Microsoft (MSFT 0.08%) is taking a new shot at Google (GOOGL -0.26%).

The world's largest software company is now directing its Scroogled.com efforts at bashing the ad-serving heart of Gmail.

Microsoft introduced Scroogled in November as a way to jab at Big G's practices. The site's first target was aimed at Google Shopping. Timed nicely to coincide with the seasonal spike in holiday shopping, Microsoft aimed to educate Internet users that Google's shopping hub consists solely of paid placement.

Was it effective? We may never know. Google had no problem growing as a company during the holiday quarter, and Microsoft's online division continues to lose money.

It probably didn't help that Microsoft wasn't exactly a saint here. Its own platform promises "higher visibility" for advertising merchants, and it was requiring merchants interested in having their products listed on Bing to go through a premium portal listing service.

Now that the holidays are over, Scroogled's new target is Gmail.

"Google goes through every Gmail that's sent or received, looking for keywords so they can target Gmail users with paid ads," the site's new landing page read. "Outlook.com is different -- we don't go through your email to sell ads."

This isn't exactly news. Users of free services expect the provider to monetize the platform somehow. Is it creepy that Google scours content to serve up relevant ads? Yes. However, if you're having an online email conversation with a friend about heading out to Hawaii next month, why wouldn't Google want to serve up a better lead by throwing an ad for Honolulu lodging options at you?

Outlook.com is free -- Microsoft rebranded its Hotmail service as Outlook.com last year -- but it's also the software giant's way to keep customers close to the premium Outlook brand and Microsoft Office software suite.

We'll see how this plays out. Microsoft is pushing out print ads this morning promoting the new Scroogled attack, and it does seem to have a better shot at working than the fading software behemoth's holiday jab.

Microsoft has plenty at stake here. This isn't just about Bing against Google anymore. As the world weans itself off PCs and embraces tablets and smartphones, we're talking about Windows losing market share to Android as an operating system.

Microsoft is taking a look at the bigger picture, and at least its shutterbug skills are improving with this attack.