Better pvp?

Serious question: Which expansion do you think has better PvP in general (disregard lolmournes): Wotlk or cataclysm? And why?

WotLK. No flying and AFKers tend to stay in Dalaran. More potential for city raids.

They are quite equal from my point of view, I've enjoyed both of them even if my favourite class (arms warrior) has passed from being one of the best pvp spec to be one of the most nerfed. Both cataclysm and wotlk pvp would be quite balanced without those overpowered pve weapons and trinkets (Shadowmourne, Fangs of the Father, Gurthalak, DBW, STS, BLF, VOS etc etc....). The classes/specs/team combos which can aim to be rank 1 are quite different but some kind of imbalance have always existed in pvp.

Passing from wotlk to cataclysm pvp (or viceversa) may be quite shocking for the first days: rogues healing themself more then you could ever expect with Recuperate, paladins being able to use Divine Shield and Avenging Wrath at the same time, retribution spec being able to deal even more bursting damage and healing more then the holy spec at the same time, every kind of tanking spec (like protection paladins and warriors) disappeared from the scenario... But in the end, after few days, you should still find your self confortable. The basis are the same: you need to know how and when to use your cooldowns and your crowd controls, the positioning, the fakecasting, the use of line of sight etc etc....

In terms of class balance Wotlk is just more balanced than Cata.
Cata has certain specs that are just better than other specs.

I think wow has no good pvp. ( Yes and still i play it )
I would go for wotlk i think. But if i want to play a pure skill based game i play something other but not wow^^