AT&T apparently liked that idea so much that it's now rolling out a similar plan in Kansas City -- where it's launching a new 1 GB fiber network that will compete with Google. The telecom said on Monday that the price of subscriptions to its network will depend on consumers' willingness to be tracked for ad-targeting purposes.

People who accept AT&T's ad targeting -- which the company calls the “Internet Preferences” program -- can purchase 1 GB service for $70 a month. People who don't want to participate in Internet Preferences will be charged $99 a month for the same 1 GB service.

“When you select AT&T Internet Preferences, we can offer you our best pricing on GigaPower because you let us use your individual Web browsing information, like the search terms you enter and the web pages you visit, to tailor ads and offers to your interests,” the company says on a site explaining the program.

AT&T says that people who sign up for Internet Preferences won't necessarily receive more ads than other users, but that the ads are more likely to relate to Web activity. 

“After you browse hotels in Miami, you may be offered discounts for rental cars there,” AT&T says. “If you are exploring a new home appliance at one retailer, you may be presented with similar appliance options from other retailers.”

The company won't collect data from secured or encrypted sites. But when users visited unencrypted sites, AT&T will collect information about pages visited, time spent on each page, search query terms, and the links and ads that are viewed and followed.

Unlike many companies that operate online behavioral targeting programs, AT&T doesn't say that the information it collects is “anonymous.” 

On the contrary, the company says that the targeted ads might arrive on email, or be sent through direct mail.

In the past, privacy advocates have challenged ad targeting by Internet service providers, which have access to almost everything users do online -- including search engine queries and activity at non-commercial sites.

Given the vast amount of data available to ISPs, some advocates have said that broadband carriers should obtain users' explicit consent before engaging in this type of ad targeting. Here, AT&T seems to be doing so -- at least on paper. Whether subscribers will read the offer's fine print, much less understand the scope of AT&T's data collection, remains to be seen.