It's been a problem ever since the dawn of my photoshop days... and just when I thought I figured it out CS4 comes along and makes it all the more confusing.
You know what I'm talking about... I got my image looking beautiful, I go to "save as" and pick JPG or PNG and I look in preview.app and my image looks different (or sometimes, if I'm really lucky, the same). But I upload it to Facebook or Deviantart and the colours are different. So I try save for web, which produces 4 different variations, none of which are the same as my image in Photoshop.
How the hell do I set this thing up so when I go to Save out my file it's the same as it looked on the Photoshop canvas?! I'll kiss you if you solve this!