Advertising and network execs say that they’ve already waited too long for the ratings colossus to figure out how to measure the growing number of people who watch TV shows on smartphones and tablets. No surprise, then, that many clients — and investors — are eager to hear the details next week when, according to the Wall Street Journal and Variety, Nielsen will disclose plans to start measuring mobile viewing in fall 2014. Some answers may depend on Nielsen’s negotiations with the Federal Trade Commission to win its approval for the company’s $1.26B deal to buy Arbitron. Nielsen said that Arbitron has assets that could help with out-of-home measurements, including the Portable People Meter that enables networks led by ESPN to account for viewers who aren’t planted in front of the living room TV.

But some investors wonder whether Nielsen will have to (at most) give that up or (at least) agree to license data to competitors as a condition to win government approval for the deal. Nielsen indicated at the end of August that it was discussing concessions when it agreed to to extend the government review into September. Even if that doesn’t factor into next week’s announcement, Nielsen probably will have to address how it will deal with its Apple problem. Mobile viewing numbers would be virtually irrelevant if they excluded iPad owners. But Nielsen’s measurement software has run afoul of Apple’s systems to protect security and battery life. The Journal says that Nielsen has filed patents for a “workaround” solution.