1. The same reason that SD entertainment looks like muddled crap on an HD-LCD/LED/Plasma television, but looks pretty good on an old CRT-television. 2. After viewing the Retina-optimized content, everything else looks like crap. (your HD television looks good when you have nothing to compare it to. However, when in a Best Buy retail store, things become difficult). WORD OF ADVICE: Try to think of your iPhone4 as a new gaming console and an HD TV, all in one. Your old (non-retina) apps are like your old console's games. They will work in the new system, but not look as nice as new releases. I experienced this with my PS3 in 2006. All my Ps2 games running on the PS3 looked like crap on my new HD TV, but they used to look very good on the SD TV. I like to call it Resolution optimization, for lack of a better term.
Your analogy is incorrect for so many reasons. Someone already explained that the reason is because it's not using nearest neighbor for upscaling.
Here http://forums.toucharcade.com/showthread.php?threadid=68035 I hope that explains. Retinasizer upscales openGL rendered games for retina display. If a 3D game still isn't running in retina after you downloaded this app, you can add games under the Library/MobileSubstrate/DynamicLibraries/Retinasizer.plist file. It's simple just do this: 1. Go to a new line BEFORE these tags </array> </dict> </dict> </plist> 2. Write:<string>com.example.game</game> (fill com.example.game with the app code you want to add) 3. Save and respring!
