For the coming expansion of World of Warcraft Cataclysm, there are lots of changes with the former expansions to satisfy the players' need. This passage i only focus on the changes of PVP and battleground in Cataclysm, in order that you can learn Cataclysm well and fully prepare for its coming.

Battlegrounds – General

Cataclysm will be Launched with two battlegrounds: Twin Peaks and the Battle for Gilneas. More to come post-release. Twin Peaks will be a capture-the-flag map similar to Warsong Gulch with a few small differences.

There will be two graveyards for each faction, with one of them being in the middle of the map. Dying out in the field will cause you to spawn here rather than at your base. It's relatively similar in size to WSG, but the field itself is larger, with the bases taking up less space.

Twin Peaks will not be replacing Warsong Gulch like some players were expecting it to.
Blizzard wants to focus on introducing new BGs to offer a variety of environments, rather than focusing on updating older ones.

Rated Battlegrounds

Players will participate in rated battlegrounds by forming their raid group prior to joining the queue. You will only face off against other rated groups. Each week the format for rated battlegrounds will be different. It will rotate between 10, 15 and 25-player battlegrounds.

Rating loss will not exist until after a certain threshold. Conquest points will be rewarded for winning rated battlegrounds. There will be a limitation on the number of Conquest points you can earn each week to prevent feeling like you must participate in both arenas and rated battlegrounds.

There will be end-of-season rewards for rated BG teams similar to arenas. The classic Honor titles will be coming back and rewarded to the top teams each season. The "Gladiator" equivalent teams will also receive epic ground mounts. Ground mounts because they want to reward something you can ride in the battleground and be proud of or show off.

Cataclysm Interrupts and Classic PvP Titles

We don't want interrupts to be binary either. They shouldn't be able to lock a caster down. We currently have something of an arms race where the melee got more mobility and interrupts, so the casters got more escape methods and instant spells. We just need some bilateral disarmament, so that melee can sometimes interrupt spells.

The designers of Cataclysm plan to grandfather in anyone with an existing BG PvP title and just let you keep it.

Source: www.wowruler.com