I strongly recommend this site called E3 Feed for finding E3 news on the games you're interested in. I've used it to comb through all the previews and interviews I could find on Borderlands, and I'm going to try to consolidate that information here so that you can see why I'm excited about this one.
The game's tone is both serious and silly. There can be spiders leaping at your face, and then there's fishing by grenade. The revamped art style has apparently helped to allow more lighthearted gameplay.
Borderlands is set on a planet called Pandora, where a massive treasure hold called The Vault has long been rumored to exist. The player chooses between one of four mercenaries who have just arrived on Pandora to find this treasure. The locals don't like you, and neither does the wildlife. Gameplay is mostly about going around killing stuff with unique weapons and chosen skills in search of more unique weapons and new encounters.
The characters you can choose between are Brick the bruiser, Roland the soldier, Lilith the siren, and Mordecai the hunter. Brick is a brawler. Gearbox's Randy Pitchford compares Roland to the Master Chief from Halo, and says he can deploy a shield with a turret on it. Lilith can "phase walk", making her invisible until she appears in the heart of enemies to release an explosion. And Mordecai is a "master sniper" with a big falcon-like creature he can send at enemies. Whichever character you select, you will level that character up RPG-style, selecting skills to develop him or her as you wish. Though I'm not 100% certain, it seems aiming is unaffected by statistics and is entirely based on player skill.
Weapons variation is similar to that in Diablo 2, with the game generating items on the fly. Even the developers are surprised by some of the weapons the players will use (that video is from January, by the way). You'll see things in this game you've never seen, like healing turrets and even healing sniper shots. Imagine your group's medic healing from far outside the firefight.
Gearbox is trying to make enemies dynamic as well. For example, that ShackNews article points out that some spiders will leap at you while others will roll toward you. There will be especially powerful versions of creatures, like the "hero" mobs of Diablo 2. From the Gamespot preview:
Groups of enemies, like loot drops, are procedurally generated, so you never know quite what you're going to get. You could get a timid pack of pup skags with a few adults escorting them. Or you could run afoul of a fierce pack of adults with a spitter thrown in for good measure. The pack we saw was headed up by a "Badass Fire Skag." Yes, that is what it is actually called.The game also includes vehicles, which can be customized. And yes, you can fight in those vehicles:
This game is as much about exploration as it is about action and achievement. And, like Oblivion, the world repopulates itself with creatures and other enemies as you kill them. From GameSpy:
One mission we saw involved a team of players cooperatively taking over a factory yard filled with bandits in order to detonate a pipeline, with frantic gunfire flying everywhere. In a nod to one of Borderlands' other inspirations, World of Warcraft, raid scenarios like this can be replayed infinitely as a nice diversion from the main story's progression.Borderlands will supposedly offer the sort of co-op gamers had hoped to find in games like Fable 2. You will be able to take your single-player mode character into another player's campaign. That's the complete open world with all of your character customizations and loot. And because the action is FPS, a level 1 character can group with a level 20 and still have fun. Up to four players can play together online, and two offline. You'll decide for yourself how to divide loot.
Borderlands is coming to the Xbox 360, PC, and PS3... this year, the devs expect. I think you understand now why this game is so high on my list. Not many games offer many months' worth of fresh gameplay, but Borderlands looks like it might do just that. Here's hoping Gearbox succeeds.