Till today, I always questioning whether Adobe Camera Raw process engine is same as the one embed inside the Lightroom. From the book Photoshop CS3 wrote by Kelby, he mentioned the ACR engine is different form the Lightroom and he stated the ACR process engine is better.
I process the Canon CR2 file shot by Canon 50D with both software, I also experimenting to convert the CR2 and DNG under Lightroom 2.2 found the CR2 conversation is sharper than DNG. The DNG file processing under ACR is sharper and obtain a more brilliant color than Lightroom.
This is my result and like to hear comments from you.