Nope.

They asked for people who played more than 1-2 hrs a week. Of those, 51% were Wii owners, etc. That's why

a) the percentages sum to a nice 51% plus 26% plus 22% = 99% (rounding error, but clearly a partition of 100%)

b) they compare it to marketshares (again rounding error, they sum to 99%)

Basically those numbers don't say that Wii owners are "more active" by virtue of 51 being greater than 26 and 22. Just that the players that declared to be "active" according to that 2hrs criterion, were distributed among consoles in more or less the same way as the marketshare, with a slight plus for Wii and PS3 and a small deficit for 360.

Or in other words: more or less the same percentage of Wii, 360 and PS3 owners plays at least 2hrs a week.

Not exactly earth-shattering, as those small discrepancies might depend strongly on the exact threshold you choose for activity.