Hey scapegoat, do you know how to write Windows software? I do, and I have actually gone through the process of making an application high dpi aware. It's much more complicated than you think, and details matter.
I see where Chris is coming from, and of course it also has to do with Adobe's willingness to spend money on development. Photoshop's development budget is not infinite and the developers are expected to do more with each new version of the product than just support new displays.
Be happy they're not just throwing Photoshop features away because a scaled up angle control won't work because of wacky Windows event handling. And don't forget that Photoshop was *just* allowed to move on past supporting Windows XP and Vista.
Not one of the other applications you mentioned does exactly what Photoshop does. They do not need just what Photoshop needs to work, nor do they have the constraints Photoshop has (for example, to be able to work in both Apple and Microsoft environments). You yourself said it: "Every application is unique."
The very fact that Photoshop now offers partially-implemented 200% scaling shows that they're on their way to implementing the support you need. These things take time. Patience is a virtue, and an informed consumer will consider evaluating needs vs. capabilities and possibly wait before jumping into new technology. I spent well over $1000 this year on a new 30" monitor and it's got... 100 pixels per inch. Why? Because I know better than to make an emotionally-driven decision to buy gee whiz tech without knowing what works and what doesn't.
All the arguments here imply that the consumer's choice to buy a gadget with high pixel density is more important that Adobe's decision to implement support for them (a minority of users) in a methodical fashion. I find that amusing.
-Noel