So what? You could doubtless say the same of the number of cyclists, bird-watchers or pot-smokers. It doesn't mean that cyclists, bird-watchers, pot-smokers or Muslims are each going to vote in one bloc: and even if they did, it doesn't follow that they would decide the outcome, since in marginal seats by definition there are many swing voters who change their vote in every election.
It makes a good headline but it's a pretty meaningless statistic.