This is no laughing matter, my friend. Emulation is pure evil. I will walk you through the philosophical underpinnings. When I'm finished, you will see that Rosetta is nothing less than a crime against humanity.
First, Rosetta *is* an emulator, even if Apple marketing doesn't like the word. I'm not even going to debate this, just go to Wikipedia and read up on Rosetta, dynamic binary translation, etc. Like every emulator, you pay a performance hit when you run an non-native app. This performance hit is about 50%. I won't debate this either, just go look at any of the benchmarks, like the Boot Camp vs OSX Photoshop benchmarks for example.
When you buy hardware that's two or three times as fast as your old computer, you don't expect it to run software at the same speed! But that's exactly what the situation is now, thanks to Rosetta.
Sure, an MBP probably runs software acceptably. But so does my PBG4 1.67ghz. In fact, a PBG4 1.67ghz will run MS Office *faster* than an 1.83ghz MBP! (See the MacTech benchmarks.) And a Mac Mini G4 will *smoke* any Intel machine in Photoshop.
The Core 2 Duo is an engineering miracle. There's no reason that someone who owns one should put up with performance on the level of a G4, thanks to a crippling emulator.
Well, at least Rosetta lets you run those old apps, even with degraded performance, right? WRONG! What if Rosetta was never released? What if Apple had just told their developers last year "Make your app universal or it won't run in six months." Everyone would have updated their app by now and the Intel machines would be the best performing systems ever made, rather than still getting owned by G4s.