Interestingly no side panel fan from TT
 

http://www.thermaltake.com/images/ca.../cooling04.jpg

this one looks eerie similar to CM Stacker: http://www.thermaltake.com/xaserCase.../va8000swa.htm

The basic is to have the largest sweeping area to carry away heat from a given surface and never forget that warm air rises.

The good design case will not only protect the components from nasty hands; coffee spill; animals but also act as "wind tunnel" to expell heat from key components.

Anything in between is merely from marketing guru and design artists to lure in $$ from the "young and restless".