Resilience was added to the game to make sure that arena PvP lasted long enough to be interesting. Inflated health pools are going to beef up the average duration of any given arena match. This is a giant plus in my book. While I'm sure many people enjoyed the Wrath of the Lich King burstfest within arena, I'm sure most arenaists want to go back to a time when games lasted longer than a Bloodlust duration.
Don't get me wrong, there's a lot to be said about coordinating a powerful burst on an enemy target. It takes a certain skill to get your ducks in a row by crowd controlling healers and getting an Immolate-Chaos Bolt-Incinerate-Conflagrate combo off. That will still exist in Cataclysm, it will just require other DPS on your team to help out.
Looking at some of the items in the beta makes my jaw drop.
If we compare this to...oh, I dunno, Shadowmourne, we see some very interesting things...DPS goes up by about 80%, the primary offensive stat is roughly 50% more, but stamina is increasing by 260%. Wow. Health pools are going to be awesome.
One of the reasons The Burning Crusade was fun because of the drastic increase in player health. Sure, your shiny Naxxramas T3 piece got replaced by a level 60 something quest blue, but that quest blue was awesome. It had stamina galore on it.
Items themselves in Cataclysm will create a PvP atmosphere of more survivability. This is needed if Blizzard wants health pools to hover between 100% and 0% more often.
Healing will also be far less powerful than it is today, which will hopefully create dynamic battles. Mortal Strike dropping to 20% around the board was a necessity and it will go a long way to creating a more balanced PvP environment overall.
Battlegrounds will balance arenas
Contrary to popular believe on some arena-focused websites, PvP is PvP. If a class is overpowered in battlegrounds, they're most likely overpowered within arenas and vice versa. Death Knights in season five are a perfect example. While they were nothing short of incredibly dominant within arena, they were equally powerful within Arathi Basin, Eye of the Storm, or Warsong Gulch.
Battlegrounds have less importance on the class composition and far more importance on overall skill and positional understanding -- it will be easier for Blizzard to make general statements about where certain classes stand based on aggregate battleground data. Hip hip hooray for better data for class balance purposes.
I imagine Battleground PvP balance will center around damage control -- making sure no one class is overly represented at the top of the leaderboards when it comes to those two statistics. While I'm sure chaining stuns together could get a nerf or something of that nature, I imagine that if shadow priests (for instance) start doing ridiculous amounts of damage around the board, they're likely to see a PvP related nerf.
Killing blows and objectives are much less telling of a class's overall power level within the battlegrounds. Healing is also a tricky one -- lots and lots of healing done doesn't necessarily mean that a class is overpowered. We'll see what will happen when it comes to PvP balance within Cataclysm.
New PvP zones
Twin Peaks is asymmetrical, and I'm not entirely sure how I feel about that. Alterac Valley has always been the most imbalanced battleground one way or the other (usually in favor of the Alliance), and if Blizzard hasn't learned from their mistakes we might see another flop.
However, barring asymmetry, the map itself looks awesome. I like multiple points of attack for each base, and the water obstruction in the center of the map will most likely keep players active near the bases. Nothing is more frustrating than being in a WSG where nine other people have an obsession with fighting in the middle.
If arena dies...
If nothing else, we'll have a new form of rated PvP. I'm incredibly stoked to see how the new battleground system works. I'm already a Scarab Lord, so I won't be salivating over the new ground mounts that are coming out for high rated battleground players, but you can be sure I'll be attempting a run at High Warlord.
Many arena players will most likely be changing guards as well, at least for a little while. It will be very interesting to see if new players try their hand at arena after jumping around in battlegrounds. I'm guessing arena representation will most likely drop from season eight to season nine. Hopefully it won't be a season five drop of epic proportions.
Once the hype about rated battlegrounds dies down a bit, we might see an overall increase in arena players that are hungry for unique titles or flying mounts.
Welcome back. I can't wait to get the best thirty or forty PvPers on my server together to form a guild. Recruiting off-server is going to be a wonderful experience too. I know lots of friends who've quit the game that are coming back if only to be in a PvP guild and do battlegrounds all the time. Owning enemies in arena or battlegrounds with friends is once again going to be a great experience, I can feel it.
Want to ascend the arena ladders faster than a fireman playing Donkey Kong? Check out WoW.com's articles on arena, successful arena PvPers, PvP, and our arena column, Blood Sport.