As with most statistics, there is no "right" or "wrong", but rather how you set up the survey as well as how you interpret the findings.
I read through the abovementioned Nielsen report and some of their other findings show, for example, 64% of iPad users are below the age of 35, which doesn't quite reflect the results of the poll on this forum. But without knowing more about how the data was collected, composition of sample size, methodology, etc, there's no way to correlate one survey finding with the other.
