Microsoft is pulling no punches in its quest to hammer Google into the ground, launching the third phase of its "Scroogled" advertising.

In a heavyweight battle of the gigantic proportions, the software maker is deep into a five-month-old marketing campaign designed to tarnish its rivals name.

And with Microsoft PR folk working over-time in over-drive, the message is loud and clear - Google sucks ass.

Well, according to Microsoft that is. But will it work?

Through "Scroogled", the company sticks the boot in, with a bold capital headline saying GOOGLE SHARES YOUR PERSONAL INFO WITH APP MAKERS.

"When you buy an Android app from the Google app store, they give the app maker your full name, email address and the neighborhood where you live," the website reads.

"This occurs without clear warning every single time you buy an app.

"If you can't trust Google's app store, how can you trust them for anything?

The campaign, which effectively encourages users to leave Google's Gmail service in favour of joining Microsoft's Outlook email facilities, was further endorsed by top personnel at the company.

"Emails are personal -- and people feel that reading through their emails to sell ads is out of bounds," says Stefan Weitz, senior director of Online Services at Microsoft in a statement.

"We honour the privacy of our Outlook.com users, and we are concerned that Google violates that privacy every time an Outlook.com user exchanges messages with someone on Gmail.

"This campaign is as much about protecting Outlook.com users from Gmail as it is about making sure Gmail users know what Google's doing."

April Fools' jokes are one thing, but direct advertising campaigns are another.

So, does Microsoft's insistence on bashing all things Google suggest a shift in industry dominance? Tell us your thoughts below