I never played vanilla, joined at TBC... BUT HOLY COW I've never experienced such clunky game play. This is primarily in regards to pvp, and I am not very geared yet, but there is probably no way I will be playing feral.
I am use to a fluid druid type game play, smoothly shifting between forms, popping HoTs then rolling around in bear for a bit, then popping back out to root and do some more healing, etc...
Vanilla its more like... Oh sh-- I have warlock DoTs on me, oh f--- cant feral charge to him and stun him, RUN AWAY and try to HoT... meh im dead....
respec to resto? resto/balance hyrbid? Wait for more gear? well see