I use DPP and use the latest version of LR (1.2) as a back up. Here is my feeling of the two programs.
DPP is faster and simpler. I think it offers more powerful sharpening, better colors, better curves feature, and it's max. size JPEG converted images are bigger.
LR is more combursome to go through and it's import/export feature is not as easy to use. I find that the colors are a bit more artificial looking and often there is a green cast that I have to remove in camera corrections. LR has a much better highlight recovery but if you do it too much a blue cast will appear. The fill in feature is nice on LR as well. You can also remove some CA, add/remove vignetting, correct tilts. The new clarity feature is nice way to selectively add contrast as well. The updated sharpening tool is better. I find the noise reduction is nicer than DPP. I do find it a bit too slow at times, as it offers more features.
So, I use DPP as a default, unless the ISO is high and I need more noise reduction than what DPP can offer, or if the lighting wasn't good and I need to do more extensive highlight recovery and fill in lighting.