[magduf]

>Why single out megachurches?

Why not? From my observations, megachurches tend to be very different from many other Christian churches, including in theology. Christians aren't all the same, but there are some definite things that many, if not most, megachurches have in common, that they don't share with other denominations. (Starting with "denominations", in fact: megachurches usually don't belong to one.)