I assume that I'm postting in the correct section, please correct me if I'm not.

So, Hello!
I'm currently in the Pre-Production/Concept Phase for my game and I need a wider opinoin for than facebook for the art direction of this game.

Here are the two styles I can't choose between:

The picture on the left was made by Effects and some purposly placed pixels and the setting of the game would be outdoors.
The picture on the right was made as an attempt at pixel art and the setting of the game would be some kind of metal ruins.

I think you might need/want some more information about the game before you give me feedback:

• The collisions are Pixel Perfect.
  
• Hopefully there will be some fuild physics.
  
• Some terrain can be destroyed.
  
• The textures are 32x32 pixels.
  
• It's planed to have things that move and a multitude of AI.
  
  So would you be able to tell me which style I should go with?
  I really need to sort this out before I can continue.

Is it purely a visual difference? The way you describe the rest of the game (particularly in reference to the per-pixel collision model) you won't see any performance difference between the two. For all I can tell, they could both be from the same game. So, what properties of each style are you expecting people to base their decision on?

Oh, sorry, I should elaborate.

The left one would most likely result in a very mario like game. You know run from left to right collecting points, dodging/killing enemys before the timer is up and a few puzzles.
While the right one would most likely result in a game that's more like metroid but has alot more puzzles to solve. It'd probbly involve more fluid movements (Wall runs and alike)

Edit: So no it's not only cosmetic it's also helps link gameplay mechanics in.
Edit2: Rewording.
Edit3: Now that I think of it a little like colbolt, with the one on the right.

and another Edit:

On the cosmetic side the one on the left requires many "transition" textures and uses alot of colours while the one on the right won't require as many transisions and so far each texture only uses 5-6 colours in it.

Well I've decided to take do a differnt style instead of these two for numerous reasons, but thank you anyway.

I know you decided on a different direction, but personally, I think the 2 samples you posted have the same style, and could easily be in the same game.
Mario vs. Abuse - that would be a real style difference.

That's pretty much what I've decided to do. I'm making them work together, better.

The main difference is that the first sample has curved, irregular slopes that are only 45 degrees on average, while the second sample has blocky stairs. Third alternative, not shown: smooth, straight slopes.All three kinds of slopes have their place in platform games, but maybe not in the same one.

• Do you want characters to run on slopes or to stop on stair steps?
  
• Do you want characters to run continuously ahead (e.g. Sonic), move freely with few reasons to stop (e.g. Super Mario Bros.), stop frequently to attack or dodge (e.g. Ghosts'n'Goblins), try difficult acrobatic feats until they succeed (e.g. certain Bubble Bobble levels)?
  Every kind of action requires appropriate scenery: Sonic has smooth ramps and even loops, Mario has open spaces with moderately sparse threats and objectives, Ghosts'n Goblins has a high enemy density and enough obstacles to add tension, Bubble Bobble has carefully designed block patterns and quasi-glitches.
  
• Do you want characters to lose contact with the ground occasionally because of bumps like the ones in the first sample, repeatedly and predictably when running down stairs like the ones in the second sample, or only when they jump or dive?
  

1. Run at a slowed pace
2. Combo of Mario and Ghost'n'goblins (A Little XD) with some acrobatics/aerobatics.
3. Preferably not across flatground but down stairs, depending on how fast they entities are traveling they might hit stairs on the way down (a bump, I guess)

This is what the third sample looks like so far, not all textures are made yet - while a few are place holders.


So i'm technicly following the third alternative at the moment.

Edit: Tiny change.