DLC comes in two pieces. First piece is the new campaign - The Passing. Taking place between Dead Center and Dark Carnival, the Survivors have come across a bridge that they can't cross. It needs to be lowered, and the controls AND motor are on the other side. There are three other survivors atop the bridge with access to the controls, but they can't lower it because the engine is out of fuel.

Fight your way to the other side - through the city, down into the sewers, and back up the other side. Talk about "that awesome biker dude", kill some mo' zombies, and learn how Bill, the Vietnam war veteran, gave his life to allow Zoey, Lewis, and Francis to escape and survive.

The second part of the DLC is Mutations, a new gameplay mode. In Mutations, the rules change every weekend, offering a plethora of possible gameplay options... and you never know what'll be next. This week, the rule is that the Survivors can't see each other, but the zombies can see you.

I played through the campaign last night, and I definitely enjoyed it. Though, I expected the L4D1 survivors to play a larger role in the campaign - at least, that's how Valve made it seem like. Now that I know they're really just cameos that you see and meet like any other NPC human in the game, I'm a little less excited about this campaign. It's a good one, but it didn't quite meet what I was hoping for. Still great fun though. I just want to see what DLC they claim to have planned for L4D1 next... likely a campaign to show how Bill gives his life at the end.

I haven't toyed with the new gameplay mode yet, but I'm going to shortly.

Is this really the first thread about the DLC? I figured there would be more. I got it yesterday and played a couple of versus modes( one being the mutation) and beat it on the campaign. I got the impression from Valve like you said that the original survivors would play a bigger part. I played it in versus first which you don't get to see any of the originals except for fallen Bill. Then I played it campaign and was like ohhh now I see.

The mutation this week is just realism versus nothing special really. Wish it could have been something other than a game mode already offered.

Left 4 Dead 2 is also currently on sale on Steam for $20.09. I'm really considering getting it.

Yeah, I'm not sure what the description of "realism versus" is about. I'm guessing it's just describing versus mode, which is kinda lame.

Anyhow, it's not REALLY anything already offered - it's a combination of realism AND versus, which you don't get anywhere else. I don't like realism mode, though, so...

I never saw Fallen Bill, but that's partially because the team I was playing against was horrible and I guess I never got to check it out. Oh well. Where is he, anyhow?

Is it always going to be Bill in the Left4Dead 2 campaign?

*sigh* They never got to have their party for getting out of the city.

He is actually right next to the generator.  So it's not like he's all hidden off in some random corner.  Just look inside the door right there with health packs and ammo table and he's on the ground holding a M16, leaned up against one of those turbine things. 

@Illegal: From the 3 times I got played he was the only one I saw.  As far as playing it from the L4D1 campaign I have no idea.  And on the poster for L4D it didn't have the silhouette of Zoey I thought, so that's who I was expecting.  I really didn't see a reason for them to have anyone die to be honest.

Oh, really? Okay, I'm gonna have to replay that part. I've played through that last stage like three or four times already and haven't seen him once. What the heck.

Realism Versus is a good game mode because it makes it tougher for the survivors. Anyone who has played L4D2 for a considerable period of time probably realizes the survivors are overpowered. This is why some people play hardcore variants of Versus that reduce health packs, tier 2/3 weapons, and beef up special infected. I've played 250+ hours of L4D2 and in my experience RV makes teamwork more important and special infected more able to inflict damage. It actually makes surviving each stage a challenge.

Actually, this guy explains it way better than me... read this - http://www.reddit.com/r/gaming/comments/bv6at/i_just_want_to_say_l4d2_realism_versus_awesome_fun/

My understanding is the voice actor for Bill is no longer available. So it would have been hard to work him into the DLC without any new lines.

I've seen killing people off for less.  I actually just checked the actor who did Bill's voice's IMDB page and it listed him as having him have Left 4 Dead 2 voice credits.  Now I don't know if it was something recent that not let him do the DLC.