It is an utterly useless and counter productive gesture. It will prompt more people to visit those pages to see what all the fuss is about and possibly more contestants in the compition.
Nobody is arguing about the stupidity of such a compition but lets not help the idiots in thier cause to defame and insult the Prophet(saw). I doubt Pakistan is going to ban it permanantly. Then the present ban can be seen as an attempt to prevent people from visiting those pages. This begs the question why a populace outraged at the contents would be visiting those pages at all.