* Is Groupon running out of money? Henry Blodget over at Business Insider does the math and concludes — among other things — that as of June 30, the leading daily deal site owed $392 million to merchants for sold Groupons, significantly more than the $225 million of cash the company had on hand. (Business Insider)

* A week after announcing an $11.8 million loss during its most recent quarter, AOL (AOL) CEO Tim Armstrong explains why his company’s turnaround will take until 2013. (The New York Times)

* Andy Miller, Apple’s (AAPL) head of mobile advertising, is leaving the company to join venture capital firm Highland Capital Partners. Meanwhile, Louie Manta, a visual interface designer on the iTunes Design team, is leaving for credit startup Square. (Fortune and 9 to 5 Mac)

* Facebook co-founder Chris Hughes sold his activism-focused social network Jumo to GOOD, a digital media platform, for what basically amounts to $0. (BetaBeat)

* Actor-turned-angel investor Ashton Kutcher guest-edited a large chunk of Details magazine’s social-focused September issue. Check out some of the results, including a round-up of entrepreneurs dubbed, “The New Titans of Tech.” (Details)

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