Giants will do battle this week as Google’s strongest competitor to-date steps into the ring.

Atlas is the re-launched ad network with an expanded, uniquely Zuckerbergian vision and a supposed answer to some of the current drawbacks facing mobile advertisers. Facebook acquired the technology from last year for a rumoured $100 million from Microsoft who purportedly shifted toward a digital services-based revenue model. There is some speculation that Microsoft saw its horse trailing the pack in the race to supplant Google and Yahoo adserving dominance, and decided to bow out gracefully. In its stead, Facebook has taken Atlas and promised to re-draw the digital media world map.

One of the biggest challenges of mobile vs. desktop advertising for marketers centers on drawing a line between consumer behavior online, offline, and in the blurry spaces in-between. Typically, when a user is served a digital ad on a desktop, their activity could be tracked by tagging their browser with a line of code known as a “cookie.” If that cookie’d user moves along the path to purchase on a given site and through the checkout window, activity is measured and attributed accordingly. If that user opts to browse or use an app on their smartphone or tablet, desktop cookies are useless.

No sure-fire way of bridging the gap between devices currently exists and, with sky-rocketing consumer mobile use, this continues to create immense anxiety for digital marketers. Add that to the hotly contested debate amongst nerds over what constitutes a reliable digital KPI and a grim picture begins to form. Cassandra-like guesswork has been a central component in determining whether digital ad revenue is being expended for a successful ROI, echoing John Wanamaker’s famous saying: “Half the money I spend on advertising is wasted; the trouble is I don’t know which half.”

Well, with Atlas, Mr. Zuckerberg and his merry band of media gurus aim to silence Wanamaker by disrupting the process.

Facebook, already one of the most visited sites on the web (and one of the most popular smartphone apps), has spent the last few years aggressively buying other mobile and tablet apps: WhatsApp and Instagram being two of the more notable acquisitions. They’ve also reportedly “partnered with all of the major apps and ad networks and exchanges” in order to draw viewed ads back to a specific user.

Using a combination of Facebook ID (which can be measured across desktop and mobile from login), mobile app identifiers, Apple and Android’s widely integrated ID systems and traditional cookies, Atlas stands to compete with Google’s DoubleClick for adserving and tracking. They’ve also linked up with search networks such as Marin for additional reach. This cocktail of digital data will, allegedly, enable Atlas to achieve greater consistency across the wide range of user experiences by creating a fluid profile that taps into multiple sources for verification.

The more points of information they can tie together, the more accurate they hope to make their media targeting between desktop and mobile. In a boon for Facebook’s bold claims, they’ve already secured the participation of the media buying behemoth Omnicom.

The big question that Facebook faces is the same one facing every digital advertiser – will it work? The proof is in the pudding. AdExchanger lists a number of shortcomings with Atlas, chief among them being market saturation. With so many data aggregation and customer relationship management technologies already available to marketers, Atlas’s incapacity to make use of some forms of existing cross-platform data will roadblock measuring campaign performance for buyers and analysts. That’s a major challenge given the urge to centralize the management of campaigns online.

Moreover, as Brian Wieser from Pivotal Research notes in Marketing Mag, the vast majority of mobile media is still being site-served rather than through third-party systems. This is in part due to the broad range of mobile devices on the market and their varying capacities to serve ads. As well, any experienced digital marketer can tell you that different adservers track impression and click numbers with huge discrepancies, sometimes leading to wildly inaccurate reporting. A higher level discussion needs to take place around whether integration across devices is even a wise direction for the industry to work toward when there is benefit to seeking optimal systems for each form of media instead of one-size-fits-all tracking.

Additionally, privacy is in the Zeitgeist, and with all the talk of digital shadows of late you’re probably feeling a little bit squeamish at this point. Indeed, The Verge asks, “Should you be afraid of Facebook’s massive new ad network?” and VICE’s Motherboard agonizes about whether, at this point, “Is There Anything Facebook Could Do to Make Us Leave?”

The answer is probably not. The thing is, if privacy is a concern to the average digital citizen, privacy is front and center for those who dance the binary-coded line between seeming creepy and relevant in delivering media to users. As with almost all modern digital adserving platforms, Facebook as repeatedly assured that Atlas will anonymize the data it collects.

So, don’t worry. There won’t be anyone connecting you by name to the ads you engage with. We’re still a long way from Tom Cruise stealing eyeballs or Facebook looking to control your life like some new-age Sandra Bullock techno thriller (did I just date myself)? Whether the platform will help in performing experiments on your emotions is a different question entirely…