Thanks to former NSA man Edward Snowden, we now know a fair amount about the NSA's ability to collect data about what people do online, and it's all rather disturbing.

But the future looks even more worrisome. Some of the biggest companies in tech are assembling new forms of online tracking that would follow users more aggressively than the open technologies used today. Just this week, word arrived that Microsoft is developing such a system, following, apparently, in the footsteps of Google.

The new data troves are to be used for advertising, not government surveillance, and only made available to authorized third parties. Yet the NSA has proven adept at co-opting large pools of data for its own ends.

"Users did not have much control in the cookie era," says Marc Rotenberg, executive director of the Electronic Privacy Information Center, a nonprofit advocacy group in Washington. "But the problem is about to get much worse – tracking techniques will become more deeply embedded and a much smaller number of companies will control advertising data."

Rotenberg says potential NSA use of the next-generation tracking data is all the more reason to move away from behavioral tracking. And he points out that there's already evidence that ad data could have been used by government spies. NSA documents published by the Guardian earlier this month appear to postulate that cookies set by the pervasive Google-owned ad network DoubleClick could be used to spot internet users who also use the Tor anonymity system.

The NSA Tor attack could only work on people who made mistakes using what is otherwise a strong system. But yesterday, Ad Age reported that Microsoft is developing a system that has intimate tracking at its core, following people as they hop from the web to apps and from PCs to tablets to phones to videogame consoles. By shoving aside cookies for an unspecified new identification technology built into devices at a lower level, Microsoft and its authorized partners would gain detailed tracking ability – though the report also says that the system could lock out non-authorized parties, who are harder to exclude from the data flow in cookie-based tracking.

That may sound like a good thing, but keep in mind that Snowden's documents indicate that the NSA has previously helped itself to big company data, with authorization or without.

Under Microsoft's system, web "search data could inform TV-style ads within streaming video apps on Xbox," Ad Age wrote. “Microsoft's cookie replacement would essentially be a device identifier, meaning consumers could give permission for its advertising use when opting in to a device's regular user agreement or terms of service." Requiring an opt-in is better than not, but the reality is that most people opt in to such things, simply because services require or encourage them to do so.

Asked about the reported tracking system, a Microsoft spokesperson passed along the following written statement: "Microsoft believes going beyond the cookie is important. Our priority will be to find ways to do this that respect the interests of consumers. We have nothing further to share." It’s not clear whether Microsoft’s system could be curbed by systems like the Tor Browser, which is designed to thwart older tracking strategies based on open standards.

Google is reportedly developing a similar cookie replacement scheme known as AdId. Indeed, large internet companies appear to be locked in something of a tracking arms race in an effort to sell increasingly targeted ads. Facebook, for example, has added advertisements based on searches and web surfing conducted outside of Facebook and even based on what groceries you buy. Still, it has relied on old, longstanding tracking techniques for which many blocking options exist. Microsoft and Google are contemplating closely held systems that could be much harder to fight.

Right now, ordinary internet users are more angry than they’ve ever been about the government sweeping their private data into big, concentrated surveillance databases. At the same time, large corporations are eagerly improving their ability to sweep private data into big, concentrated advertising databases. At the very least, Microsoft and Google will have to walk a fine line to deploy these systems. But perhaps this time, the protests will be louder – and more effective.