Sorry for not responding sooner, I got home very late yesterday and crashed on the couch from exhaustion. I will reply to everyone that had a question or a comment. Except a giant reply.

killzone 2 looks great but i still think from everything i have seen of killzone 2 vs gears of war 2 that gears still looks better.

With the exception of a few developers that have been quoted saying the Cell processor is not that hard to work on, the vast majority think it is difficult. Even with times, developers may become more accustomed to developing for the Cell processor, but it is still not an easy thing. They have to spend more time planning things out and more time implementing those things. There are a few programmers that just having something "click" in their heads and they are able to take a difficult task and flawlessly optimize it for the Cell processor. However, those developers are rare (No, not Microsoft's rare :D)

http://www.eurogamer.net/articles/hirai-were-the-official-industry-leader

In this 1/09 article, a Sony exec claims that the Playstation 3 was designed to be difficult to program for. While I think this is just a way to try and get good PR out of the fact that the Cell processor is difficult todevelop for, I think it's more realiable than random developer saying "xxxxxx" since opnions vary. This is coming from Sony itself.

EDIT: Oops, I pasted the wrong thing earlier. I like to write my responses in a text editor and paste them here.

I think this goes back to the arguement you have to sacrifice one thing, for another.

You can have either a more varied game with more impressive geometry (such as Gears of War 2) or more impressive textures. At least for now, anyways.

Every decision sacrifices one thing for another. Neat read.

Haha, don't let Guerilla Games hear that, they will hunt you down and force you to watch their GDC presentations! Killzone 2 was more difficult to develop due to the Cell processor and new engine they wrote around the processor.

There are a lot of different methods to make shadows. Some of them require little power and look bad, some of them require a moderate amount of power and look good, and other require a lot of power and look amazing. Most games go for moderate/good or little power/decent. Real shadows are extremely power intensive and can cut a game's FPS by half.

However, you can also use fake shadows (shadows are already fake, I guess this would be fake fake shadows). Lets say you have a light in an otherwise completely dark spot. Instead of having a light there and having the engine do the math for it 30 times per second, you could edit the texture of the wall too look as if they had a light on them and just stop processing the math for that wall. When the character gets near, then they may switch back to the normal mode and no one knows. The same trick can be applied to shadows, just apply simple post-processing or easier, just make the game dark from the start. Dark games can be made to look better easier than light games can.

Speedtree would not fit well into the Killzone 2 and would cause a major performance hit. If Guerilla could have taken speedtree, lighting engine xxx, mesh engine xxx, particle engine, xx and stuck it together and released a game that looks just as good in 12 months, you better believe they would have. However, in order to have Killzone 2 look the way it does, they have to do everything by hand and use hacks to make it look the same as more power-intensive algorithms. Trees are one of the hardest things to fake and still have look good. Guerilla Games would have had to make serious sacrifices in order to put trees in here, luckily, they didn't have to. I bet there will probably be at least a few trees in the game, but even then, I don't expect them to look as good as the rest of the game. If they had trees, they would have spent an hour talking about the technology as that is something which a lot of developers have been interested in.

I've said from the start that Killzone 2 looks great and that the Playstation 3 is more  powerful than the Xbox 360, whoever, I still maintain that Killzone 2 is the result of effort, not that power gap.

Also, procedural synthesis is very tricky on the Cell processor since you take tiny instructions and generate massive amounts of data with them. The SPEs don't have enough local storage and would have to send everything via the bus. So in essense, it really isn't that well fitted for procedural synthesis, although I am sure it can be done at the sacrifice of other things. 

Sorry, I must have missed that one. Again, I have already addressed this several times. The number of animations and on-screen enemies really isn't that impressive. Epic Games showed over 140+ hordes on the screen at the same time in GoW2 with their own animations, collision detection, etc.  However, Killzone 2 does have more different animations than Gears of War 2, but that doesn't really take up that much power, it just takes more effort to make all those animations. The particles and other FX in Killzone 2 are very impressive though, and like I've stated before, I think that is something which other advanced game engines would sweat a bit doing.

Although art style is only one consideration, I am arguing that art style + level design(which I bundled into art style but address in this thread as well) is one of the major things that help Killzone 2 look the way it does. What other large consideration would the developer have to make? I know there are a lot, but I simply want to know what you're thinking of. They may not be as big as you think they are. 

What I said is true though, Killzone 2's art style is easier to develop for than GoWII's art style. There may be other considerations, but that does not make my argument any less valid.

I only read page 12 of this thread.I haven't played either and since I have little technicl knowledge/experience,I blindly agree with everything jetrii said.LOL!

@ jetrii

I think the majority of your Killzone 2 screens are old. Could be wrong, but I remember seeing those quite a long time ago.