Is the (Shadow)Priest the better Mage in WOW?

[Xanthix]

Probably just my own biases from having played a paladin, but it seems to me that:
best CC + best AoE > your paladin four any day

Does a class need to be the best at something to be desired in groups? Some classes are good because they can fill multiple roles, even if they are not the best at an individual role. Pallies have great (if not the best) buffs, are great (if not the best) at tanking and off-tanking, have good (if not the best) healing, and can res too.

For a party I may first want to secure a tank, a healer, and some DPS, but after that I would definitely prefer a utility class to another tank/healer/DPS. I think some classes are excellent support classes, able to fill-in wherever needed to keep a party running smoothly.