So far, there doesn't appear to be a way to view how many individual people have logged in to the new place. Here are some stats on the network's traffic for the 14 days it's been back open, the 14 days before it was closed, and the same 14 days last year.
Since reopening:
August 7th, 2013 - August 20th, 2013
6188 visits
3,053 unique visitors
9.81 pages per visit
60K pageviews
Average duration: 9:23
Same dates last year:
August 7th, 2012 - August 20th, 2012
15,556 visits
10,429 unique visitors
3.51 pages per visit
49K pageviews
Average duration: 2:57
Before closing Ning:
Jun 28th, 2013 - July 11th, 2013
11,441 visits
7,842 unique visitors
3.12 pages per visit
35K pageviews
Average duration: 3:09
Since reopening, the amount of individual pages viewed, pages per visit, and average duration has increased dramatically, compared to both past date brackets at the Ning hideout.
Ads are seen by people that are not logged in. And, regardless of how many people log in or view the site at any given time, your ad runs until it reaches those views. Whether it takes 1 day or 60 days to reach that many views.
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