An interesting assessment that I've heard from someone who would have reason to know is that Groupon is moving towards pivoting away from the "Daily Deal" business and monetizing their network of small business relationships using a different business model.

That would explain the reduction in ad-spend on end-user acquisition. If my sources are correct, we'll see something new popping up in the next 120-180 days from our friends over at Groupon somewhat unrelated to the coupon business.