[enoptix]

I question the accuracy of these numbers. Hitwise, Quantcast, Comscore, etc, all use sample data and extrapolate their numbers based on these figures. Often the data is gathered using toolbars that are installed as part of another software package.

I work in search marketing and I can't tell you how many times Comscore or Hitwise has said a clients web traffic has taken a dive, even though the real on-page analytics are reporting the opposite. It's very frustrating that people take these numbers at face value.

[AJ007]

From what I've seen first hand on my own websites' ad inventory along with what my $$ ad intelligence tools tell me, Groupon's US ad impressions have dropped off a cliff in the past few months. As of halfway through this month they basically stopped buying display ad inventory -- this is from the US side of things. I think they are buying more display internationally (which I am no expert on.)

Hitwise, Quantcast, Comscore, by themselves don't mean too much. When you combine them all together and you look at traffic numbers for really giant web sites they are pretty close to being accurate.

I was pretty optimistic about the daily deal sites, but Groupon (and LivingSocial to a degree as well) pulling back on their ad campaign coverage so dramatically is not a good signal. The other competitors that were spending early on (late last year) did not last very long, and it was a good signal of things to come.

Groupon has a great business model, but as with any business model that relies on buying tons of ad inventory it raises your profile too big too fast. That in exchange explodes your ad costs and eliminates your margins. At the end of the day Google and website publishers end up the winner. That's one of the reason I've split my business across lots of different websites. Had I not, I don't think I would have been able to keep it running profitably.

Update -- here is something to take a look at. Earlier this year InAdCo was running display campaigns on behalf of Groupon on a massive scale, chances are if you were using the internet you saw these ads more than once(they had some fancy in-ad signup form) If you take a look at their traffic on quantcast it had a huge spike April-May and then went to nothing http://www.quantcast.com/inadcoads.com The traffic returns in May, but as I recall it was pushing LivingSocial at that point. Their traffic has dropped off again, with neither Groupon or LivingSocial to be seen.

[robryan]

They were wasting a stack of money promoting their Australian site stardeals though the google display network before they even had any deals on the site for people take up. Sure I get the strategy of trying to build up a mailing list so the initial deals will sell really well but as with most things they do it's throwing a boatload of cash down now hoping they can build up some sort of defensible mailing list.

[mikecolella]

Compete and Alexa also both show a traffic drop since June. It's unlikely that they are all wrong. Also, all of these services are most accurate with big traffic sites such as Groupon.

[tedjdziuba]

Next time you go to the doctor, ask him to take all your blood instead of just a sample.