Basic ideas:
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Typical "ideal" floor should be a low-shag carpet or commercial carpet.
  Elimin8r: An option, but not *required*.
  Good for moving games.
  Reduces static electricity problems that may be present.
  NOTE: Static is caused by low humidity. Shaggy carpeting will make a problem worse.
  Holds its shape very well.

Carpeted floor panels / carpet tiles
  Same as above if commercial, low shag.
  Simple replacement of damaged areas. 

Specialty carpeting
  Static resistant carpet
  Carpeting with patterns which reacts strongly to blacklight.
    http://www.kidcarpet.com/carpetstyles/blacklight.html

Blacklight rugs
  http://www.childrenscarpet.com/Back%20Light%20all%20thumbs.htm
 
Vinyl tiles
  Prone to tearing, damage.
  No worry of static.
  Absolutely not preferred.
  Very hard on the feet when standing and playing games for a period of time.

Cement floor
  Little worry about cleanup.
  No worry of static.
  Very hard on the feet.

Wood floor
  Prone to damage
    Very easily scratched when moving games.
    Weight of games making dents in the floor
  No worry of static.
  Very hard on the feet.
  Probably the worst possible choice in arcade flooring.

Section of raised flooring
  A section that is raised above floor level.
  Can be used to highlight special games.
  Allows more games to be seen at a glance. No hidden back-row.

Raised datacenter floor tiles
  Absolutely no idea -- not known to have been done.
  Easily hides wiring.
  Can distribute air conditioning from below into specific spots of the room.  
  Industrial / technological look.