[meritt]

Groupon has simply gotten big enough they don't have to advertise as aggressively, especially in search advertising. Their partnership with AdParlor via Facebook is also running very strong.

Groupon all along has been bringing in substantial cash but also spending a huge amount towards marketing. They've saturated their markets in the US. They can now drop that marketing budget and see massive profits in their US business.

[cadwag]

That would be like saying "since everybody already knows about Apple and their products and they are bringing in substantial cash, they can cut their spending." But instead, Apple has been increasing their ad spending as revenue has gone up http://gw5.appleinsider.com/article/?id=14437 (bit old, but still holds).

Personally, I know that I only reach for a groupon or a coupon of any sort when it's shoved in my face. For them to make such a drastic shift amidst questionable profitability on exactly the first day of a new quarter makes me inclined to agree with the author and say that it's a strategic shift in direction.