...when looking at third-party services such as comScore to assess unique users or time spent the aggregated figures may not tell the story of what’s happening and the key, value-creating starting points for consumers and advertisers. Our internal logs show that the metrics we’ve discussed with you in the past, such as uniques and page views, continue to grow in the double-digits in Q4 with unique users now topping 500 million and page views about 4 billion per day.
With consumers accessing the web in so many ways, we’ve looked for a more unifying global metric that’s more flexible across Yahoo!’s and our partners’ properties and useful across multiple devices and geographies. We expect to use visits to Yahoo!’s global starting points and anchor sites to be the most relevant metric going forward.
Visits are defined by comScore as the number of times a unique person accesses content within an entity and they capture the fact that consumers may visit a property multiple times a day from different locations or devices; not just whether they touched a site once per month.
Larry Dignan writes:
On the conference call there were a few key takeaways that are worth noting. To wit: ...Decker kicks Comscore. Decker noted that Yahoo’s page growth was growing at a double digit clip in contrast to what Comscore is reporting. Welcome to the club Sue. Decker noted that the company is using visits instead of page views and unique users as a more appropriate metric for Yahoo’s key properties.
Here's the full YHOO earnings call transcript.