It depends what type of PVP you are interested in - arena, world, or battlegrounds.
Ranged damaged classes are the most popular when solo'ing in any of the above 3. I believe hunters are under represented in the higher ranking arena teams, as often a warlock or a mage is preferred for their increased versatility. (It also depends on the brackets, in 2v2 you will see a lot of combinations and I have seen hunters perform very well there).
For healing I believe druid to be the most powerful. Disc healing priests have also turned up a fair amount as well. Paladins are still exceptionally useful - I use mine in battlegrounds mostly and my priest for arena. In the world, I really don't have a choice and always try to make sure that they're in suitable equipment.
Being sad is the same thing as giving up.