Resto Shaman in cata: It's more challenging, you have to manage your mana and not so much chain heal spam anymore and healing rain is cool.
Ele shaman in cata: It feels like wotlk again tbh. I just keep spamming the same button and see big crits, earthquake is mana draining and do shit dmg?
Enhancement shaman in cata: Havent it, but it looks awsome :P
All in all imo: Resto shaman is more fun now then it used to be.