Myth or not, the technology's been around for some years[1] [2], and there's a profit to be made from matching consumers and advertisers. One doesn't really need to run voice analysis, just pick a keyword[3] every now and then. You add two and two.
>would be a PR disaster for either company and cause legal action too.
Didn't stop Sony [4], and didn't cost them all that much in money - on the order of $1MM - or reputation either.