The problem is... they're not even really great at BG/PvP.

Hunters' defenses are all very active, not passive like shamans or pallies. Managing feign death, deterrence, disengage, etc on multiple characters is awful.

Oh yeah, and you're useless when a melee infiltrates your team.

There are a few little tricks that they can do well, but not enough to justify actually playing them anymore. 4xslowing traps in AV at a choke point WAS fun pre-WotLK, though!